Here is something I worked out years ago that helps me do the math in my head. I double the Celsius, subtract 10%, then add 32. So, in the first example; 20 doubled is 40. 40 minus 10% is 36. 36 + 32 = 68.
@@ocralez3637 I struggled trying to multiply by 1.8 and adding 32 in my head. One day it dawned on me that doubling and subtracting 10% was the same as multiplying by 1.8. Once I realized that, I could convert in my head in seconds. In my supply chain career, I became faster than the engineers and their calculators!! And that was really COOL!😄
@@irynaYe This estimating method doesn't work as well for negative numbers as it does for higher positive numbers. As far as logic, Celsius is also an just arbitrary scale superimposed on the freezing and boiling points of water. People just get used to the numbers on the scale they are accustomed to for weather temperatures, etc. so logic doesn't really matter.
Almost the entire world uses Celsius. But we Americans have to stick to our Fahrenheit. It's a little insane. But my interest is personal. Two of my adult children are living in European countries and I want to be able to easily convert temperatures when we're chatting about the weather. This was so so helpful, Thank you very much!
yeah uh huh... Try cooking in Celcius,. Buy a chicken by the kilogram and set your oven to 176c. You can't because chickens are sold in the USA by the lb, and ovens are in F. The math to convert shows that F is 5/9 of C, meaning that F has more precision, great for cooking. Still want to swap to metric? There are ~280 million cars on the road in the USA. Suppose you change all the signs to Kilometers. Do we expect that every driver of a car older than the metric adoption needs to calculate how fast they are going because their speedometer is still in miles? It would take a monumental effort on every American's part to shift to metric and cost billions of dollars. Other than being like the rest of the world what do we gain from it? I'm not against Celsius for scientific purposes (or anything metric for that matter), but Fahrenheit is just easier for every day use.
@@diviosdi8065are you high? You can convert Kilo’s to Lbs easily with this channel. Also most major car manufacturers put KP/H on the speedometer until recently. And if you have a digital speedometer you can change it to KP/H, cuz its built in. We’re not the only ones in the world who drive on the wrong side of the road. Its a conversion of maths ideals, not some tech that has to be converted ya div. Cars are made for the world economy and arent even made in America, only assembled so they can keep telling the lie about the American jobs they exported.
Ok this is actually super helpful. As a new US expat in France I struggle all the time with the Celsius temperature. Thanks for this much easier to remember formula!
Thank you so much for explaining this video in a way that's simple to understand. I have had dyslexia or word processing disorder for as long as I can remember and now that I still have it in my adult years (and going into the medical field) and trying to understand myself and how my brain works has been a challenge for me but since taking what I have seriously and working around it by learning the way I receive information has helped me out tremendously! The way you broke this formula down, step by step, dissecting the context was amazing to me. It felt like I had a breakthrough and the feeling of "understanding" that I got from this video, gave me hope that I can convert in my head, without the use of a device or someone else helping me. I struggle on a daily and try not to let it show to others and this content made me feel like it was designed just for me. So, thank you for making these videos! I will continue watching your content and learning from your easy-to-understand video. Thanks again!
I took the practice quiz to the link you provided, and I scored 100%. I honestly couldn't remember the conversion method if I didn't look it up to work out my problems. This method is easier to remember. Thank you so much.
I’m taking a certification test where I’ll have to do this with multiple choice. THANK YOU!!! This is going to make it EASY! I’m terrible memorizing formulas
VERY helpful! You are great at systematically teaching in a simplified manner. Awesome job! And as far as converting temperatures goes, estimating is pretty much all that is needed (save medical temps).
OMG!! this is SO amazing! Thank you so much! I've struggled with this for many years when we travel! I'll share how I estimate kilometers to miles: if not round number, round up, divide in half and "add a little!" gets you pretty close! (e.g., 95 km rounds to 96 mi ÷2 = 48 plus add around 10 = 58 (actual answer is 59) - the greater the number of km, the more you have to add - however, I do NOT recommend this for figuring how fast you can drive! but not bad for figuring approximate distances!
Hey thanks. That's great. Simple and easy. My wife ask me all the time how hot or cold it is and if it's gonna rain. Now I'll start doing this swap on her. With the rain, I already tell her it's a 50 percent chance. It either will or it won't.
The way i convert c to f or vise versa is by knowing that 10°c is 50°F, and if you go up 10°c you go up 18°F or down 10°c you go down 18°F. And if you want to make it even easier like he does, make the 18 a 20
I got this super quick, im shocked i dont get math EVER!the letters acted somewhat as a guide or.. at any rate it worked! I'm 46 & FINALLY I won't be completely lost when hearing a reference to a temp in Celsius, Thank You so much! You must be a genius, it takes real intelligence to simplify these things in a way people like myself can grasp so quickly, Thank You!
Nicely put. I feel like I watched way more than I needed to , just so I could explain it as well to someone else. But I liked how you go to hole numbers to break it down. Nice Video ,I could easily watch more.
The most accurate and yet still simplest means to the answer is F° =2C° -(10% of the preceding multiplication)+32° F° = 40 -4+32 F° = 68° 40°C =2(40) - 8 +32 = 104°F You can do it all in your head. I know I can.
I do something similar, but more accurate. I think of 1.8 as 2 - 0.2. So after I double I subtract 10% of the result, since 0.2 is 10% of 2. So 20 x 2 = 40. 40 - 4 = 36. 36 + 32 = 68.
That is a cool way of doing this. I am from the US and I chat with my friend in Canada frequently. She will tell me it is 20c and I will have to google to see what it is. Now I don't have to. Thanks!
I to liked your video it helped me in the exam and I scored full. My teacher is also not teaching me so deep. She just start the exercise. I wish you were my maths teacher. Thank you so much 😊😊
So for celcius you can get ur final number and then subtract. So if 50 celcius comes out to 130 and its actually 122. Count your tens after 50. So 60 is 1 and 70 is 2 and 80 is 3 and all the way to 130 then subtract the 8 form 130 and you get 122.
In otherwords, 2c+30-(2c+30-c)/10 Simplifying to.. 19/10*c+27 which is NOT the same as 9/5*c+32. In fact these equations intersect at c=50 so your "trick" ONLY works if you're trying to convert 50⁰ Celsius to Fahrenheit. It doesn't work for any other number.
I loved your teaching, I wish I had someone like you when I was growing up. You're fabulous. All that said, as someone who deals with this regularly I found an easier, faster way that you might like. Here goes. Today in Ireland it's 11 Celsius at 8am. I double that 11 and add 30. It is 52 farenheit which is almost exactly the farenheit number of 51.8. Reversal from farenheit is easy too, if its 70 farenheit and I want celcius then 70 minus 30 leaves 40 split in half is 20. 20 celcius is really 68 farenheit so not too far off (and here that's a bit of a heat wave. Lol.) I think my down amd dirty approach gets a good appropriate though without too much bother. Let me know if you see a flaw. I think it's not as good with larger temperatures but I live here so that's maybe ok with me. Have a lovely day and thank you again. Please keep posting. Love your style.
Thank you so much for this, sir. I struggle mightily with simple math, and have to google every time I set my A/C or want to know the temp outside. I truly appreciate you taking the time to make this… from a 48 year old woman :)
This was super helpful! I'm traveling to Europe soon and trying to figure out the temp is frustrating. Your way of going from C to F is super simple! Double C plus and extra 30. (I'm remember the E as EXTRA...it just works for my brain.) Thank you!!
This is great thank you. I wanted to add a little for those who might care. Without your help I would never have figured this out! I have to take my shoes off to count over 10. Grin. Although your formula is a great idea, the answer gap starts to widen when trying to convert unusually high celsius temps like oven temperatures! What if the quiz said 170° C equals??? The differential between the original formula and your suggested formula is quite large… You would be 370°, which is quite a gap between the original formula which comes out to 338°. Since 9/5 is 1.8; it is 10% higher than 2, and it's so much easier to use your suggested 2, how about taking your given Celsius of 20 and reducing it by 10% before anything else just leaving the 32 as is? Ex 20-10% = 18 2(18) + 32 = 68 And using the oven temp… 170° -17° equals 153° degrees. 153° times two equals 306°. Adding 32° to that equals 338° which is exactly what the original formula would have done. Adding the extra math in is difficult I know but it may help when a quiz has two answers that are way too close together.
Thank you sooo much for your informative video 🙏🏻 I almost gave up on how to do C to F or vice versa. I found it hard to memorise the formula until I watched this video 🙃 God bless you for making one hurdle less in my brain 🙏🏻
Very nice and easy explaining. I always forget but I hope this will make me remember. I have tried various approaches to remember but by far this is the best approach. I hope you can make another advanced video to give an idea about when to add a couple of degrees or subtract to provide an even closer conversion.
I'm studying for an exam tomorrow, and we're supposed to know how to convert Celsius to Fahrenheit and vice versa. This was incredibly helpful! Thanks a lot!
At first I was confused, but then I realized it's just either doubling then adding 30, or going backward in the same linear sequence by subtracting 30 then halving. Thanks!!
Thank you for the formulas. I learned this in grammar school, but after 55+ years I could not recall how to break it down unless I flip my weather app from F to C and C to F, when sharing temperatures information with a relative in Mexico.
Thank you sir, I play a lot of European and Canadian video games and the Celsius instead of fahrenheit is tricky. They really should have taught this better in school!
Good video, and how about examples of winter freezing temperatures like minus 5° C because that requires being mindful of dealing with both negative and positive numbers in the same formula. So, going from - 5° C, to °F, using video's easy "A B C D E F" formula, approximates ( - 5 x 2 ) = - 10, and ( - 10 + 30 ) = + 20 ° F. So in winter, a minus C temp can equal a plus F temp. And, of course the other way around also holds. So, converting from + 20 ° F to C, gives - 5 ° C. I.e., (+20° F - 30) = -10. And (-10 ÷ 2 ) = - 5 ° C. 😊
@ I prefer the most accurate calculation possible, rather than rounding, unless the decimal is smaller than thousandths, such as anything beyond the “6” in 1.896 Accuracy is just that important to me in math.
Thank you! I've got a cousin in the States and we're always converting our temps. Might need to do some brain work so it sticks but before you're lesson I know 20C is about 70F.
Ok. This maybe works for small numbers, under 100. But for oven temperature for example 180ºC x2+30 = 390ºF. But Google converter gives 356ºF. And it is a big difference.
I lived near Canada, and listened to Canadian radio stations, which I would get a estimate conversion by multiplying Celsius ✖️ 2, and add 32. My baseline 0° 6:44 × 2= 0 + 32 = 32° F. Yes, it is close estimate, but exact about freezing. 37°C is 98.6, I would then get a closer estimate comparing my answer to this.
man besides information is right there everywhere pretty much and really does it matter if it says Celsius or Fahrenheit when it's 120 outside we f****** know it's hot
As you get up into higher numbers (e.g., oven temperatures), this trick doesn't work as well. Using the trick in the video, 180C converts to 390F. But using 9/5C+32 yields 356. So it's off by 34 degrees. I don't know where things start going askew in a major way, but as a certain point, it seems like 2C yields a closer result than 2C+32. For example, 180C converts to 360 using 2C, much closer to the precise formula.
Another method is to double the C, subtract 10% and add 32, i.e., 20 x 2 = 40, 40 - 4 = 36, 36 + 32 = 68. I find multiples of 10 easier to think about than calculating by 9/5.
Obviously being 60 now, we didn’t start learning the metric system in Kindergarten so as a young teen, I already had a bit of problems in math. I was Great when it came to the basics, adding, subtraction, division and multiplication.. Until we started with fractions.. everything over and beyond was terrifying to me, no matter who tried helping me…. So we had one teacher (not a math teacher) told us that one way to convert from Celsius to Fahrenheit was quite simple, however not exact, it would work some what like this Gentleman was learning us, with a multiple choice answers not exact.. but it’s pert near the same. He said to double the number and add 3O.. so 3O*C-❓F would be 30x2+30=90 the exact answer is 86 which to me.. much MUCH simpler than this Gentleman’s way of doing it. I actually had trouble and had to watch the process a few *cough cough* times (4😳)
If 0° C = 32° F (freezing point) and 100° C = 212° F (boiling point) why, using your simplified shortcut, does 100° C = 230° F? Am I doing something wrong or is being off 18° F close enough?
It helps to remember what Fahrenheit is...the same thing as Celsius & Kelvin. They're three temperature scales just shifted...with Fahrenheit has the further difference that each 1 degree of centigrade is 1.8 degrees of Fahrenheit. Ex: Boiling point of H20 minus Freezing point in the two scales is: 212 - 32 = 180 vs. 100-0=100; that Fahrenheit is shifted by 32 degrees, i.e. the freezing point is 0 in Celsius but 32 in Fahrenheit. This makes conversion simple, ex: just do D.S.S.! A temperature in Celsius(ex: 15C) just: 1. D.ouble it. (15x2=30) 2. S.ubtract it. (OR "Subtract 10%" whichever you remember easiest). (30-3=27) then 3. S.hift it. (Add 32...or add 30 then add 2.) (27+30=57; 57+2=59) Again: 1. D.ouble it. (15x2=30) 2. S.ubtract it. (OR "Subtract 10%" whichever you remember easiest). (30-3=27) 3. S.hift it. (Add 32...or add 30 then add 2.) (27+30=57; 57+2=59) Your answer: 15C=59F! Hooray! Note the quick math here, ex: to multiply something by 1.8 (which is 180% of something), an easy "tip calculation" way to do this is just to double the number(take 200% of) then subtract 20% But 20% is double of 10%, so it's so easy, ex: 15 x 1.8 = 27. You can do it in your head in seconds. 15 x 2 = 30 then minus 3 because 3 is 20% of 15, but it's also 10% of 30=15x2 which makes the conversion simple. To multiply something by 1.8 just double & subtract 10% of that number. Actually the fraction helps to illustrate this, ex: 1.8 is 9/5. If it were 10/5 it'd be multiplication by 2 a.k.a. twice as much, but 9/5 is twice as much minus the 1 out of 10 is 10%. ;-) Also, even faster sometimes: I just remember that Celsius degrees are about twice Fahrenheit degrees and you start from about 30. Ex: 0C is about 30F (32-2) 5C is about 40F (41-1) 10C is about 50F (this is the exact match, i.e. 10C=50F) 15C is about 60F (59+1) 20C is about 70F (68+2) 25C is about 80F (77+3) 30C is about 90F (86+4) 35C is about 100F (95+5) 40C is damn hot! (This is where the 1.8 being a little less than twice catches up to you, ex: 35C is really 95F not 100; 40C is 104F) But a "dirty" way to do this: just round the degree centigrade temp to the nearest 5; degrees F is that times 2 plus 30. Or don't even round just double and add 30 gets you close for temps in common weather range. The 30 being less than 32 somewhat compensates for 9/5ths of something is slightly less than twice something.
There's an even more accurate way albeit a little more mental work...but just a little. Use this formula instead: 2 * C + 32, less a "subtractor." In this example, step one is C=20*2=40 Then add 32 = 72 total. Now refine. Divide the original C temp by 5 (20C/5 = 4). Subtract 4 from the prior total of 72 and you get 68. If there's a remainder when dividing by 5, you can do a little estimating and get it really close. Example what is 22C in F? Double it = 44 then add 32 = 76. Save that #. Then divide 22 by 5 and you get 4 and some change. Subtracting 4 from 76, you get 72. The exact answer is 71.6! (this is actually close enough, where for most practical applications, you can stop here). If you want to get more accuracy Since 22 is about half way to the next increment of 5 (i.e. 25), split the difference and add 0.5 to the amount you subtract. That means you can estimate it like this: 76 (original # to save), then subtract 4.5 (instead of just 4) and get 71.5 degrees F (remember the actual answer is 71.6?). Your estimate is only 0.1 degrees F off! Being more exact matters if you're planning to go out somewhere, where a couple of degrees C is the difference between say, a light jacket or a sweatshirt, or perhaps nothing extra is required. This is the method I came up with living in Japan. Once you practice this a few times, by writing it out, it becomes very simple to do in your head. Stop reading here, if you're happy with this accuracy. Read more if you'd like to get it even more precise. Once you've got the hang of it, you can get a more exact (be exactly on, down to the tenth of a degree) but requires one more step that you can do in your head. We know we have to subtract a number, the example of 22C, we estimated the subtractor will be 4 + 0.5. To be more exact keep the 4 as the subtractor, but instead of estimating the difference caused by the remainder, simply come up with a more precise "additional" subtractor (0.5 as in the previous estimate), add 0.2 degrees, for every degree of the remainder, to the final subtractor. Keeping with this example you'd keep the initial 76 degrees. Then you're going to subtract (4 + 0.2 degrees for each degree of the remainder). 22/5 = 4+(0.2 times the 2 degrees left over, or 0.4. This means instead of adding the estimated 0.5 degrees to the subtractor (4), you will add 0.4 to 4 and you get 4.4 to subtract. This means the original # saved (76) minus 4.4 degrees = 71.6! All of this sounds complicated, but a little practice with some paper at first, and you'll get the hang of it. All of this works for all temperatures.
This is great and well written. But I have to say.. I think the point was to eliminate an equation you have to memorize. Your example, although more accurate, requires more memorization than the initial equation he presented at the beginning that no one wants to remember.
I grew up in F and then we had to convert to C as an adult. My body knows what Fahrenheit temp feels like, but for Celsius it doesn't have a clue. 60F, I know what that feels like on my body, having that converted to Celsius just tells me what the number is in C. I sometimes have to convert C into F so I know how the temp will affect me. Old school people will never truly completely convert, the brain says, nope!!
I never got through transition math in high school 😂 I just couldn’t understand fractions for the life of me! Yet my dad was a literal genius who was apart of Mensa. He was a firefighter, a pharmacist and a mathematician in his lifetime. Makes me feel very small that it missed a generation. Luckily all my kids have his brains lol
![Convert Celsius & Fahrenheit Temperature Scales in Chemistry & Physics - [1-1-4]](http://i.ytimg.com/vi/7IALrswAnxs/mqdefault.jpg)
Here is something I worked out years ago that helps me do the math in my head. I double the Celsius, subtract 10%, then add 32. So, in the first example; 20 doubled is 40. 40 minus 10% is 36. 36 + 32 = 68.
woow thanks pal really useful 👍
@@ocralez3637 I struggled trying to multiply by 1.8 and adding 32 in my head. One day it dawned on me that doubling and subtracting 10% was the same as multiplying by 1.8. Once I realized that, I could convert in my head in seconds. In my supply chain career, I became faster than the engineers and their calculators!! And that was really COOL!😄
Best way I've found; thank you!!
Bro, your way is brilliant because it's NOT an estimate, it's an EXACT answer !!!! 🙀😸👌
Well done!! Thx
4 years in highschool and I NEVER understood this formula, less than 10 minutes watching this video and I understand it 100%.
Great video! Excelent for like the weather forecasts and such.
C -> F : Double and add 30
F -> C : Subtract 30 and half the result.
Not exactly, -40 C = -40 F
No it is not!!
According to this formula -50°C should be -70F?
It is actually -58°F
F° does not have any logic in it, what a lovely system to use
@@Vbluevital He said in the video his formula is an estimate. Exactly, it's 1.8C + 32= F , so -40 C = -40 F, the only temperature where they match!
@@irynaYe This estimating method doesn't work as well for negative numbers as it does for higher positive numbers. As far as logic, Celsius is also an just arbitrary scale superimposed on the freezing and boiling points of water. People just get used to the numbers on the scale they are accustomed to for weather temperatures, etc. so logic doesn't really matter.
@@irynaYe "lovely". Fº doesn't make any sense at all.
Thank you for breaking down the math in simple terms. You have a gift of teaching. I wish you were my math teacher growing up. Great job.
That's what I just said to myself. Math and I don't get along 😅
I rarely comment on videos, but this one really deserves it. Thank you so much. 😄
I wish YOU had been MY teacher back in the day! Thank you for making this conversion so easy to remember and accomplish! Great job!
Almost the entire world uses Celsius. But we Americans have to stick to our Fahrenheit. It's a little insane. But my interest is personal. Two of my adult children are living in European countries and I want to be able to easily convert temperatures when we're chatting about the weather. This was so so helpful, Thank you very much!
yeah uh huh... Try cooking in Celcius,. Buy a chicken by the kilogram and set your oven to 176c. You can't because chickens are sold in the USA by the lb, and ovens are in F. The math to convert shows that F is 5/9 of C, meaning that F has more precision, great for cooking. Still want to swap to metric? There are ~280 million cars on the road in the USA. Suppose you change all the signs to Kilometers. Do we expect that every driver of a car older than the metric adoption needs to calculate how fast they are going because their speedometer is still in miles? It would take a monumental effort on every American's part to shift to metric and cost billions of dollars. Other than being like the rest of the world what do we gain from it? I'm not against Celsius for scientific purposes (or anything metric for that matter), but Fahrenheit is just easier for every day use.
I've used F all my life and I'm not going change now.....
@@michaelporter2574 nobody i expecting you guys to change, trust me.. 😅
@@diviosdi8065are you high? You can convert Kilo’s to Lbs easily with this channel. Also most major car manufacturers put KP/H on the speedometer until recently. And if you have a digital speedometer you can change it to KP/H, cuz its built in. We’re not the only ones in the world who drive on the wrong side of the road.
Its a conversion of maths ideals, not some tech that has to be converted ya div. Cars are made for the world economy and arent even made in America, only assembled so they can keep telling the lie about the American jobs they exported.
@@diviosdi8065you are never ever gonna use that much precision in cooking. Don't delude yourself. Adoption is always gradual.
Where has this been my whole life!? Thank yOu!
😢
Ok this is actually super helpful. As a new US expat in France I struggle all the time with the Celsius temperature. Thanks for this much easier to remember formula!
Thank you so much for explaining this video in a way that's simple to understand. I have had dyslexia or word processing disorder for as long as I can remember and now that I still have it in my adult years (and going into the medical field) and trying to understand myself and how my brain works has been a challenge for me but since taking what I have seriously and working around it by learning the way I receive information has helped me out tremendously! The way you broke this formula down, step by step, dissecting the context was amazing to me. It felt like I had a breakthrough and the feeling of "understanding" that I got from this video, gave me hope that I can convert in my head, without the use of a device or someone else helping me. I struggle on a daily and try not to let it show to others and this content made me feel like it was designed just for me. So, thank you for making these videos! I will continue watching your content and learning from your easy-to-understand video. Thanks again!
I took the practice quiz to the link you provided, and I scored 100%. I honestly couldn't remember the conversion method if I didn't look it up to work out my problems. This method is easier to remember. Thank you so much.
I’m taking a certification test where I’ll have to do this with multiple choice. THANK YOU!!! This is going to make it EASY! I’m terrible memorizing formulas
You are amazing math teacher. I wish I had math teachers like you back in high school. Thank you so much for sharing your knowledge with us.
VERY helpful! You are great at systematically teaching in a simplified manner. Awesome job! And as far as converting temperatures goes, estimating is pretty much all that is needed (save medical temps).
OMG!! this is SO amazing! Thank you so much! I've struggled with this for many years when we travel! I'll share how I estimate kilometers to miles: if not round number, round up, divide in half and "add a little!" gets you pretty close! (e.g., 95 km rounds to 96 mi ÷2 = 48 plus add around 10 = 58 (actual answer is 59) - the greater the number of km, the more you have to add - however, I do NOT recommend this for figuring how fast you can drive! but not bad for figuring approximate distances!
Genius! Understood by the end of the video. Perfectly explained.
This is so helpful & taught in a way both my children & I can understand. Thank you so much!
Just what I needed! I've been getting in some tourist Spanish, Italian, and Portuguese, but forgot to account for C vs F. Thanks!
Hey thanks. That's great. Simple and easy. My wife ask me all the time how hot or cold it is and if it's gonna rain. Now I'll start doing this swap on her. With the rain, I already tell her it's a 50 percent chance. It either will or it won't.
It takes almost 10 minutes to tell us how to figure it out in 5 sec - 10 sec in our heads...😂😂😂 (Actually did a great job!!)
The way i convert c to f or vise versa is by knowing that 10°c is 50°F, and if you go up 10°c you go up 18°F or down 10°c you go down 18°F.
And if you want to make it even easier like he does, make the 18 a 20
I got this super quick, im shocked i dont get math EVER!the letters acted somewhat as a guide or.. at any rate it worked! I'm 46 & FINALLY I won't be completely lost when hearing a reference to a temp in Celsius, Thank You so much! You must be a genius, it takes real intelligence to simplify these things in a way people like myself can grasp so quickly, Thank You!
Nicely put. I feel like I watched way more than I needed to , just so I could explain it as well to someone else. But I liked how you go to hole numbers to break it down. Nice Video ,I could easily watch more.
The most accurate and yet still simplest means to the answer is
F° =2C° -(10% of the preceding multiplication)+32°
F° = 40 -4+32
F° = 68°
40°C =2(40) - 8 +32 = 104°F
You can do it all in your head. I know I can.
I do something similar, but more accurate. I think of 1.8 as 2 - 0.2. So after I double I subtract 10% of the result, since 0.2 is 10% of 2. So 20 x 2 = 40. 40 - 4 = 36. 36 + 32 = 68.
I do this also. It works great. How do you do it from F to C?
I go 20x9÷5+32=68
That is a cool way of doing this. I am from the US and I chat with my friend in Canada frequently. She will tell me it is 20c and I will have to google to see what it is. Now I don't have to. Thanks!
Thank you so much for your videos, they’ve been a tremendous help to me going through my ST program.
Yes. I love tricks like this. It helped get me through nursing school and has stuck with me, but I never knew one for this. Thank you.
I to liked your video it helped me in the exam and I scored full. My teacher is also not teaching me so deep. She just start the exercise. I wish you were my maths teacher. Thank you so much 😊😊
So for celcius you can get ur final number and then subtract. So if 50 celcius comes out to 130 and its actually 122. Count your tens after 50. So 60 is 1 and 70 is 2 and 80 is 3 and all the way to 130 then subtract the 8 form 130 and you get 122.
In otherwords, 2c+30-(2c+30-c)/10
Simplifying to.. 19/10*c+27 which is NOT the same as 9/5*c+32.
In fact these equations intersect at c=50 so your "trick" ONLY works if you're trying to convert 50⁰ Celsius to Fahrenheit. It doesn't work for any other number.
really awesome way to teach this trick, i could've benefit from my teachers in past if they could simplify the way you do. for real, props to ya!! 😭😅
I loved your teaching, I wish I had someone like you when I was growing up. You're fabulous. All that said, as someone who deals with this regularly I found an easier, faster way that you might like. Here goes. Today in Ireland it's 11 Celsius at 8am. I double that 11 and add 30. It is 52 farenheit which is almost exactly the farenheit number of 51.8. Reversal from farenheit is easy too, if its 70 farenheit and I want celcius then 70 minus 30 leaves 40 split in half is 20. 20 celcius is really 68 farenheit so not too far off (and here that's a bit of a heat wave. Lol.) I think my down amd dirty approach gets a good appropriate though without too much bother. Let me know if you see a flaw. I think it's not as good with larger temperatures but I live here so that's maybe ok with me. Have a lovely day and thank you again. Please keep posting. Love your style.
Thank you so much for this, sir. I struggle mightily with simple math, and have to google every time I set my A/C or want to know the temp outside.
I truly appreciate you taking the time to make this… from a 48 year old woman :)
This was super helpful! I'm traveling to Europe soon and trying to figure out the temp is frustrating. Your way of going from C to F is super simple! Double C plus and extra 30. (I'm remember the E as EXTRA...it just works for my brain.)
Thank you!!
That was the coolest and easiest way to understand Fahrenheit to Celsius and Celsius to Fahrenheit thank you
You're INCREDIBLE for this. Thank you thank you. Studying for the MCAT here.
This is great thank you. I wanted to add a little for those who might care. Without your help I would never have figured this out! I have to take my shoes off to count over 10. Grin.
Although your formula is a great idea, the answer gap starts to widen when trying to convert unusually high celsius temps like oven temperatures!
What if the quiz said 170° C equals???
The differential between the original formula and your suggested formula is quite large… You would be 370°, which is quite a gap between the original formula which comes out to 338°.
Since 9/5 is 1.8; it is 10% higher than 2, and it's so much easier to use your suggested 2, how about taking your given Celsius of 20 and reducing it by 10% before anything else just leaving the 32 as is?
Ex 20-10% = 18
2(18) + 32 = 68
And using the oven temp…
170° -17° equals 153° degrees.
153° times two equals 306°. Adding 32° to that equals 338° which is exactly what the original formula would have done.
Adding the extra math in is difficult I know but it may help when a quiz has two answers that are way too close together.
Thank you sooo much for your informative video 🙏🏻
I almost gave up on how to do C to F or vice versa. I found it hard to memorise the formula until I watched this video 🙃 God bless you for making one hurdle less in my brain 🙏🏻
Very nice and easy explaining. I always forget but I hope this will make me remember. I have tried various approaches to remember but by far this is the best approach. I hope you can make another advanced video to give an idea about when to add a couple of degrees or subtract to provide an even closer conversion.
This F to C, C to F conversion has bothered me for decades and today it has became a fun thing to do in head now!
I'm studying for an exam tomorrow, and we're supposed to know how to convert Celsius to Fahrenheit and vice versa. This was incredibly helpful! Thanks a lot!
I hope you didn't have a negative value in the exam like -40C
Very cool way to convert AND work the brain a little ;)
At first I was confused, but then I realized it's just either doubling then adding 30, or going backward in the same linear sequence by subtracting 30 then halving.
Thanks!!
Thanks for the great helpful advice love it .Hi from South Australia Adelaide 🇦🇺
Wow! Thank you SO much. I have always felt at a loss with this conversion...not anymore! Best--
Very helpful . . . and nicely done! Thank you for posting.
Thank you for the formulas. I learned this in grammar school, but after 55+ years I could not recall how to break it down unless I flip my weather app from F to C and C to F, when sharing temperatures information with a relative in Mexico.
Thank you sir, I play a lot of European and Canadian video games and the Celsius instead of fahrenheit is tricky. They really should have taught this better in school!
Omg this is amazing I paused the video and did the math and played it and got the answers right!!!! 🎉thanks so much
As we use Farenheight here in the US, traveling to Europe uses Centigrade, and I usually struggle what is it in F. Great trick to do it easily.
Brilliant. Thank you so much for sharing this great trick for ball parking these conversions.
Mannnnn, you made my life easy.. love this trick 😍
Good video, and how about examples of winter freezing temperatures like minus 5° C because that requires being mindful of dealing with both negative and positive numbers in the same formula. So, going from - 5° C, to °F, using video's easy "A B C D E F" formula, approximates ( - 5 x 2 ) = - 10, and ( - 10 + 30 ) = + 20 ° F. So in winter, a minus C temp can equal a plus F temp. And, of course the other way around also holds. So, converting from + 20 ° F to C, gives - 5 ° C. I.e., (+20° F - 30) = -10. And (-10 ÷ 2 ) = - 5 ° C. 😊
9/5 is 1.8, so 1.8C+32=F so you can just multiply C by 1.8 rather than multiply by 9 and then divide by 5.
Assuming I’m understanding this correctly.
Who is multiplying by 1.8 in their heads? 😄 Easier to multiply by 2. That's his point
@ I prefer the most accurate calculation possible, rather than rounding, unless the decimal is smaller than thousandths, such as anything beyond the “6” in 1.896
Accuracy is just that important to me in math.
Thank you so much, I've been trying to memorize the formula for ages:)))
So 2 times Celsius plus 30 We'll get you within a couple degrees of the actual temperature very useful thank you
Thank you for this, I need this method to dumb it down for me.
Thx a lot Dude, now i know how to convert from C to F. You gave a really good explanation
Thank you!!! I understand math horribly but it makes sense when you explain it.😊
Omg. This is freaking amazing. Thanks so very much 🙏🙏🙏
Thank you! I've got a cousin in the States and we're always converting our temps. Might need to do some brain work so it sticks but before you're lesson I know 20C is about 70F.
Wowwwwww thank you sooooo very much
I can’t believe it this is so much earlier to remember. God bless you
Thank you sooo much for this clarity!!
Your method thought me a lot I am in 5 th grade and I am studying from u for my final exam so thank you 🎉❤
THANK YOU! It can't get simpler than this!
Ok. This maybe works for small numbers, under 100.
But for oven temperature for example
180ºC x2+30 = 390ºF.
But Google converter gives 356ºF. And it is a big difference.
The earlier poster who subtracts 10% from the original answer before adding the 30 works really really well👏👏👏
Why not 1.8(180C°)+32 =356F°
Very well explained. Thank you
Awesome explanation, makes it really simple. Thanks for sharing
Extremely helpful! Thank you so much for sharing this!
OMG !! This is exactly what I needed. Thank you so much.
Thank you, this was very helpful 👍
You're a genius!! Thanks so much. You made it super easy, even for someone, like me, who is math challenged!! 😅😊
This a good for approximating under 100°c then it requires adjustment to stay close
I lived near Canada, and listened to Canadian radio stations, which I would get a estimate conversion by multiplying Celsius ✖️ 2, and add 32. My baseline 0° 6:44 × 2= 0 + 32 = 32° F. Yes, it is close estimate, but exact about freezing. 37°C is 98.6, I would then get a closer estimate comparing my answer to this.
Thank you! I've never been taught this. I appreciate it so much.
I wanna say thank you for making this video it really helps me youre my math hero😊
Thank you , this is brilliant ! Never stop learning and all the best :)
man besides information is right there everywhere pretty much and really does it matter if it says Celsius or Fahrenheit when it's 120 outside we f****** know it's hot
As you get up into higher numbers (e.g., oven temperatures), this trick doesn't work as well.
Using the trick in the video, 180C converts to 390F. But using 9/5C+32 yields 356. So it's off by 34 degrees. I don't know where things start going askew in a major way, but as a certain point, it seems like 2C yields a closer result than 2C+32. For example, 180C converts to 360 using 2C, much closer to the precise formula.
Thanks! Math is so amazing when you know the best path.🎉
Brilliant! You're a great teacher! Thankyou
Wow, this was a great video and clever trick! I subscribed!!
You teach math like I teach my boys math, very helpful! Ty!
Another method is to double the C, subtract 10% and add 32, i.e., 20 x 2 = 40, 40 - 4 = 36, 36 + 32 = 68. I find multiples of 10 easier to think about than calculating by 9/5.
Thanks Mr. Teacher!
Love the CDEF mnemonic!! Thanks!
Just multiply the Celsius by 1.8 and add 32. This gives you the exact temperature. Everyone has a calculator on their cell phones.
19x1.8+32= 66.2
Obviously being 60 now, we didn’t start learning the metric system in Kindergarten so as a young teen, I already had a bit of problems in math. I was Great when it came to the basics, adding, subtraction, division and multiplication.. Until we started with fractions.. everything over and beyond was terrifying to me, no matter who tried helping me…. So we had one teacher (not a math teacher) told us that one way to convert from Celsius to Fahrenheit was quite simple, however not exact, it would work some what like this Gentleman was learning us, with a multiple choice answers not exact.. but it’s pert near the same. He said to double the number and add 3O.. so 3O*C-❓F would be 30x2+30=90 the exact answer is 86 which to me.. much MUCH simpler than this Gentleman’s way of doing it. I actually had trouble and had to watch the process a few *cough cough* times (4😳)
That is brilliant. Thank you.
I use this to go C to F. (C x 2 x 0.9) + 32 = F Example: 20 x 2 = 40, 40 x 0.9 = 36, 36+32=68
Just two remarks: “Wow!” and “Thank you!”
If 0° C = 32° F (freezing point) and 100° C = 212° F (boiling point) why, using your simplified shortcut, does 100° C = 230° F? Am I doing something wrong or is being off 18° F close enough?
It helps to remember what Fahrenheit is...the same thing as Celsius & Kelvin. They're three temperature scales just shifted...with Fahrenheit has the further difference that each 1 degree of centigrade is 1.8 degrees of Fahrenheit. Ex: Boiling point of H20 minus Freezing point in the two scales is: 212 - 32 = 180 vs. 100-0=100; that Fahrenheit is shifted by 32 degrees, i.e. the freezing point is 0 in Celsius but 32 in Fahrenheit.
This makes conversion simple, ex: just do D.S.S.! A temperature in Celsius(ex: 15C) just: 1. D.ouble it. (15x2=30) 2. S.ubtract it. (OR "Subtract 10%" whichever you remember easiest). (30-3=27) then 3. S.hift it. (Add 32...or add 30 then add 2.) (27+30=57; 57+2=59)
Again:
1. D.ouble it. (15x2=30)
2. S.ubtract it. (OR "Subtract 10%" whichever you remember easiest). (30-3=27)
3. S.hift it. (Add 32...or add 30 then add 2.) (27+30=57; 57+2=59)
Your answer: 15C=59F!
Hooray!
Note the quick math here, ex: to multiply something by 1.8 (which is 180% of something), an easy "tip calculation" way to do this is just to double the number(take 200% of) then subtract 20% But 20% is double of 10%, so it's so easy, ex: 15 x 1.8 = 27. You can do it in your head in seconds. 15 x 2 = 30 then minus 3 because 3 is 20% of 15, but it's also 10% of 30=15x2 which makes the conversion simple. To multiply something by 1.8 just double & subtract 10% of that number. Actually the fraction helps to illustrate this, ex: 1.8 is 9/5. If it were 10/5 it'd be multiplication by 2 a.k.a. twice as much, but 9/5 is twice as much minus the 1 out of 10 is 10%. ;-)
Also, even faster sometimes: I just remember that Celsius degrees are about twice Fahrenheit degrees and you start from about 30.
Ex:
0C is about 30F (32-2)
5C is about 40F (41-1)
10C is about 50F (this is the exact match, i.e. 10C=50F)
15C is about 60F (59+1)
20C is about 70F (68+2)
25C is about 80F (77+3)
30C is about 90F (86+4)
35C is about 100F (95+5)
40C is damn hot! (This is where the 1.8 being a little less than twice catches up to you, ex: 35C is really 95F not 100; 40C is 104F)
But a "dirty" way to do this: just round the degree centigrade temp to the nearest 5; degrees F is that times 2 plus 30. Or don't even round just double and add 30 gets you close for temps in common weather range. The 30 being less than 32 somewhat compensates for 9/5ths of something is slightly less than twice something.
There's an even more accurate way albeit a little more mental work...but just a little. Use this formula instead: 2 * C + 32, less a "subtractor." In this example, step one is C=20*2=40 Then add 32 = 72 total. Now refine. Divide the original C temp by 5 (20C/5 = 4). Subtract 4 from the prior total of 72 and you get 68.
If there's a remainder when dividing by 5, you can do a little estimating and get it really close. Example what is 22C in F? Double it = 44 then add 32 = 76. Save that #. Then divide 22 by 5 and you get 4 and some change. Subtracting 4 from 76, you get 72. The exact answer is 71.6! (this is actually close enough, where for most practical applications, you can stop here).
If you want to get more accuracy Since 22 is about half way to the next increment of 5 (i.e. 25), split the difference and add 0.5 to the amount you subtract. That means you can estimate it like this: 76 (original # to save), then subtract 4.5 (instead of just 4) and get 71.5 degrees F (remember the actual answer is 71.6?). Your estimate is only 0.1 degrees F off!
Being more exact matters if you're planning to go out somewhere, where a couple of degrees C is the difference between say, a light jacket or a sweatshirt, or perhaps nothing extra is required. This is the method I came up with living in Japan. Once you practice this a few times, by writing it out, it becomes very simple to do in your head. Stop reading here, if you're happy with this accuracy. Read more if you'd like to get it even more precise.
Once you've got the hang of it, you can get a more exact (be exactly on, down to the tenth of a degree) but requires one more step that you can do in your head. We know we have to subtract a number, the example of 22C, we estimated the subtractor will be 4 + 0.5. To be more exact keep the 4 as the subtractor, but instead of estimating the difference caused by the remainder, simply come up with a more precise "additional" subtractor (0.5 as in the previous estimate), add 0.2 degrees, for every degree of the remainder, to the final subtractor.
Keeping with this example you'd keep the initial 76 degrees. Then you're going to subtract (4 + 0.2 degrees for each degree of the remainder). 22/5 = 4+(0.2 times the 2 degrees left over, or 0.4. This means instead of adding the estimated 0.5 degrees to the subtractor (4), you will add 0.4 to 4 and you get 4.4 to subtract. This means the original # saved (76) minus 4.4 degrees = 71.6! All of this sounds complicated, but a little practice with some paper at first, and you'll get the hang of it. All of this works for all temperatures.
This is great and well written. But I have to say.. I think the point was to eliminate an equation you have to memorize. Your example, although more accurate, requires more memorization than the initial equation he presented at the beginning that no one wants to remember.
I grew up in F and then we had to convert to C as an adult.
My body knows what Fahrenheit temp feels like, but for Celsius it doesn't have a clue.
60F, I know what that feels like on my body, having that converted to Celsius just tells me what the number is in C.
I sometimes have to convert C into F so I know how the temp will affect me.
Old school people will never truly completely convert, the brain says, nope!!
This was really helpful. Thank you!
So helpful! I appreciate you sir!
Very useful, nice video
The real way to do it accurately is
cx 1.8 +32 😊
Thank you very much I fully appreciate it.
Huh ? I feel as dumb as I did 45 years ago in math class, that went right by me.
I never got through transition math in high school 😂 I just couldn’t understand fractions for the life of me! Yet my dad was a literal genius who was apart of Mensa. He was a firefighter, a pharmacist and a mathematician in his lifetime. Makes me feel very small that it missed a generation. Luckily all my kids have his brains lol
Don't feel bad...me too