Sir, I am 60 years old and love math but have forgotten the basic operations to solving problems, haven't really had to do these in over 40 years, I appreciate your videos, lessons to get me back to what I once could do! Thanks
I know how you feel my friend I'm 61 I haven't done this kind of working years some of it I didn't do it All.. I went to high school in the seventies back then algebra was not a mandatory class I never had it
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The same but a little bit more logical way: 5^6 = 5*(5^5) 5*(5^5) - 1*(5^5) / 4 = 4*(5^5) / 4 = 5^5 It's like 5 apples - 1 apple level math problem. :)
Yes, I see a picture and "notice" that (as you point out) 5^6 is 5 times bigger than 5^5 and transpose it to 5x - 1x over 4 = 1x or 5^5. I wondered if you "saw" that or "worked it out" if you see what I mean.
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@@cliff481 I see this two ways simultaneously. As 5^6 and as 5*5*5*5*5*5. So, I can not unsee the fact that 5^5 or 5*5*5*5*5 is part of 5^6 like 5*(5*5*5*5*5). I hope it helped. :)
Thank you for explaining several ways to do each problem and taking your time instead of rushing through.This is excellent for young children just learning and also for senior citizens that are brushing up on things that they haven’t done in years!Teaching math so that the student really “gets it” takes a special skill!Thank you!
The objective is not getting the correct answer. Rather, it's about learning the concepts which may be applied to more difficult questions. Some students are only interested in having the answer without any knowledge or understanding to resolve the problem.
Ok so I am 50 yrs old and math has never been my subject. But let me say in this one video I learned more than I have known all these years. Somehow you made it so easy for me to understand. Thanks.
Another *excellent* point being made at 10:16 is "you have to consider who you're learning math from"! Kudos, @tabletclass 👍👍👍 I think that many/most of us are aware of the difference between being taught-by-rote versus being challenged to THINK. With the-LATTER as teacher, one can often IDENTIFY one's weak spots WHILE RESOLVING them. Well... if one takes the time to do so... 🙂
I am glad you explain the problem in detail. Math is my weak spot. I can do it but been 20+ years since I took a College math class. ( I returned to college in my 50s) so had to start all over practically. NIW I enjoy these to keep my brain working.
GOOD & thank you!😁😁 At 1:22 a definition of "multiple choice" is stated: "1 of these is the correct answer". This means *exactly 1* correct answer, ie no less than 1 correct answer & no more than 1 correct answer. One can validly *DEDUCE* from it that "all answers except 1 are NOT correct".
Then there is the D answer that is A & C are correct. Just not usually in math, 17 A) is odd B) is even C) is prime D) both A and C D is most right but the others are STILL correct so your hypothesis is absolutely wrong since only B can be eliminated. I assume you do not do well in tests.
If you do not really appreciate this teacher’s work, why do you waste your time here, criticizing and badmouthing? Please know that there are people who appreciate Mr John’s teaching and let them benefit from his work.
Tip..... If you want to help anyone in maths.....1. Get to the Point , 2. Get to the Point , 3. Get to the Point!!! Stretching a 1 minute session for 15 mins or more would take people many years to get past junior grade at that rate !!!!! Most people including myself would much prefer a direct simple approach rather than take a walk around the garden to see what's there!!! You're not helping anyone stringing them along like you are!!!
He's trying to give reassurance and encouragement to those unsure of how to proceed. Those (me and I'm sure thee!) who can see what to do at a glance, don't need this. We already have a justified confidence! Not all have that luxury/accomplishment.
@@davidwright8432 Reassurance, encouragement and even build confidence in people, these are all good, but stretching it out like this does not, build confidence, reassure or even encourage, when lessons are dragged out like this...... Dragging them out like this, lessons are more likely to instill impatience and frustration by.... Not Getting To The Point In A Timely Manner !!!
I left school in 1969. I did maths in several engineering coursed up to Honours degree level over many years. I still find your explanations thorough and interesting. I could solve this problem easily, most engineers could, but undoubtedly most of us engineers, especially those, like me in their eight decade, likely would use a calculator. Funny that considering that calculators did not exist when I was at school. I am sure I would have been taught how to factorise the equation at school but I didn't remember it and I enjoyed being reminded.
This video (15+ minutes) is way way too long for the problem. The majority of the of the time has nothing to do with how to solve the problem. If you're watching these videos to help improve your SAT or ACT scores you'll never get there.
(5^6 - 5^5) / 4 It is very tempting to just say 5/4 but 'to the power of' doesn't work like that. So .. let's express 5^6 as 5^5 x 5 so that they are both 5^5 ((5^5 x 5) - 5^5) / 4 which is also (5^5 x 5) - (5^5 x 1)) / 4 which can be changed to 5^5 x (5 - 1) / 4 5^5 x 4 / 4 and 4 / 4 = 1 giving us 5^5 as the answer.
@@frenchimp It's interesting you should say that .. because my mathmatics teacher at school (back in the 70s) always used to say ''Now, it's very tempting to just say'' before going on to explain why something was wrong, and in this case I was just pointing out one of the things that people could get wrong before going on to answer the question. If you think that means that I ''have no idea what mathmatics is about'' then I won't do it again .. however, after 50 years, it may be too late to tell him.
I put it in a calculator. Gives a actual 5^5 value 3,125 This is why this stuff is way super confusing to many. It doesn't answer as "5^5" . Many fail to see the need for such mental gymnastics
@@jeffwells641 No. Sadly I stumbled on it and mistakenly thought it would be entertaining. It’s too hard to watch with all the bullshit drawings and windy commentary. I wont waste any further time with these vids.
@@michaeld2662please make sure not to stumble hereafter, because your badmouthing our teacher, does not help us, who really appreciate his work. Life is too short and we have to find ways to live respecting each other in harmony.
If it's not acceptable to the OP, somebody wants you to follow some rule that makes sense only to the person arriving at the alternative solution, and to the people who also follow that rule. There are plenty of similar maths puzzles online where people differ owing to their following different rules. Maths is NOT a black and white discipline, where there is only one correct solution for each problem. If you want to do well in maths class, learn what rules that particular teacher wants you to follow.
@@phildavenport4150: Since 3125 IS 5**5, what the hell are you babbling about? It's NOT a different solution than all the comments using algebra, factoring out 5**5, and getting 5**5 as the answer. It's just doing the problem directly with good old basic pre-algebra arithmetic, like we did in middle school, 50 years ago.
This is how I did it too. But the 3125 breaks down to 5^5 so that’s the answer I committed to. Which appears to be correct but this method seems to be incorrect?
As an engineer, I work with several people who didn't pay attention in math classes, but were somehow promoted to the next grade anyway. They think I'm some sort of math god because I can solve problems like this in less than a minute.
Yeah, when I transferred schools for 9th grade they had me take the PSAT with the 11th and 12th graders. I did not know about the minus 40 or I would have had a 790 since I answered them all, as it was my lousy 760 beat everyone but 1 chicken senior who skipped a few questions. They let me take the advanced algebra after those results.
I got it by making a chart of 5 to the 1st through 5 to the 6th. Then i just did the simple arithmetic. I couldn't remember how to work with exponents, but that worked and didn't take too long.
Here's what I did: 5^2 = 25, 25 × 25 = 625 (4th power), 625 x 25 = 15,625 (6th power). 15,625 - 3,125 (ans/5) = 12,500 Now that we know the top answer is 12,500, divide it by 4, you get 3,125 which, surprise, is the 5^5 answer we had earlier.
It might not always be the right answer for solving math problems, but if I don't know right away what to do I will typically factor the numerator first then the denominator and see if it simplfiies the equation or allows for cross cancelling.
3,125 was the answer I came up with while doing this calculation in my head. I was correct. Although, this answer of 3,125 is not an option in the video. The video shows the answer is 5^5. This is correct. However, 5^5=3,125. So, the ultimate answer should be 3,125.
They wanted you to apply the logic he demonstrated rather than plugging away at the math, I agree it does not take much longer but the question is testing n=your ability to for application not how fast you can multiple. I was working it out and pause when I saw (5-1) / 4 which equals 1. I did the multiplication in my head and then saw this relationship which you missed.
The problem is you were possibly taught that on the other side of an equal sign is supposed to be an 'answer'. That is false. On the opposite side of any equal sign is EQUAL WEIGHT. It can be expressed as simply, or as complex as you would like. If the equal weight is supposed to be in a particular context, it is so stated in the question/problem. What if the multiple choice contained BOTH 3,125 and 5^5? Then clarification about what form the weight was required to be in would be needed. In this case, 3,125 was not an option, so 5^5 was the only valid equal weight. You say that 5^5 = 3,125 - which is true. Then you say that the answer should be the right side weight (3,125). Well, an equal sign works both ways (because ultimately it is a BALANCE point), so.. 3,125 = 5^5. According to your logic of where we obtain 'the answer', now your answer should be 5^5. The 'answer' is not in the equation, it is within the multiple choice selections.
@@michaelzoran that assumes the author didn't screw up. These internet posting are often done by people who cannot solve their own posts. I admit that I only looked at the correct response without evaluating it as it fails as an identity though it works for these specific answer. My answer turned out wrong and that is notbthe end of the universe.
I wish I had a Algebra teacher in JH like you, I failed. Come in college I had great teachers and did great but the things we worked on a Calculator wouldn't help you any(this was the 80's) unless you knew how to work the problem. Most of the "what is the correct answer" you see on TH-cam are not formatted correctly so they create a argument, Mathgirl did a great video years ago covering this..
My answer is 5 to the fifth power. The numerator can be considered as 5 to the fifth times (5 - 1) ; that is 5 to the fifth times 4, and as the denominator is also 4, the fours cancel. leaving 5 to the fifth.
I skipped forward, you know TH-cam has a little control on the bottom. You seem to know nothing about how to use TH-cam. Maybe that tutorial should be next on your list.
@@FoodNerds If he got it right immediately and he knew it was right, you're right, it is his fault to "waste his time". I think he needed to make sure his method was correct in attaining his answer.
I know you said "No Calculator" John, but I had to see how my phone's cheapo calculator would deal wit this. Even when putting parentheses around the exponents, it gave incorrect answers. I had to use EQUAL sign before dividing by 4 to get it right. I'm an old fan of RPN logic, on the HP with an ENTER key but no = key. I never get wrong answers with my HP 41C. But I've never found a phone with RPN in the calculator program.
Learn so much from your videos Thanks for doing this . What would you say is the ratio of grateful people to ungrateful ? Just a rough estimate I really want to know. ❤
Did this in my head in less than 30 seconds using the long way, got 3125 so picked E … Would have used your method if it wasn’t a simple number like 5’s … 5’s are too easy to do in your head! … In my head I multiplied by 10 then divided by 2 …. 5*5 =25 250/2 = 125, 1250/2=625, 6250/2=3125, 31250/2=15625 …. Took the 3125away from the 15625 easily in my head to get 12500 then just halved it twice 6250 then 3125 which was the 5th of my 5’s so got 5to 5th in under a minute with no writing down … does this make me weird? Doubling and halving is too easy … even the subtraction was easy … so I chose the easiest option.
The answer is E. 5^6 = 5 * 5^5 = 5^5 + 5^5 + 5^5 + 5^5 + 5^5. If you subtract 5^5 from that, you stil have 4 of them. divide that by 4 and you get 5^5.
I used a calculator cause my brain doesn’t brain real well sometimes and I got 3125, which turned out to be A correct answer, but not the answer your looking for. It’s the same as Hello is to G’Day is to Hi, different words, same intent.
i am now retired, it’s good to see these problems again. though i have to say, throughout the years, i never had to solve nor ever came across a problem that i had to use this operation. i still can’t think when i’d be using it.
Absolutely guess at answers if you don"t kno and if wrong answers aren't penalized. Then there's the quick screen to throw out obviously wrong answers to improve probabilities.. AND Always attack problems you KNOW how to do and then go back after those you aren't sure. Never waste time on something that confuses you until.AFTER you've answered easy-to-you questions.
Please do this for me 🙏 Kate likes to walk down moving escalators and she takes one step at a time. When she walks down at a rate of 2 steps per second, she reaches the bottom from the top after 18 steps. When she is exhausted, she will walk down at a rate of 1 step per second and she will reach the bottom from the top after 12 steps. Find the time- taken for her to reach the bottom from the top if she just stands on the escalator.
Well, 5^5 is (5^3)^2 = 125^2 which is going to be up around 15,000. 5^5 will be a fifth of that, or around 3000, subtracting it brings us down to 12000-ish. Divide by 4 gets us to 3000-ish. 5^4 is 25^2 = 625, so the only answer here remotly big enough is e, 5^5. It took me a lot longer to type than than to think it - I probably went through it all in 6-7 seconds.
I never understood powers math and after watching this 5 times I’m still confused. Would you make one that only goes through the solution the correct way? I’m 70 & have never had to deal with powers except in math classes. That said, I’d really like to know how to do it. I vaguely recall a math teacher saying something like add the exponents together. I just don’t remember why.
I got the answer e) 5⁵ by taking out the common factor of 5⁵, but it's hard to get your head around the fact that the difference between 5⁶ and 5⁵, is 5⁵ multiplied by 4.
Those of us who are natural mathematicians will always fast forward John's videos. Consider yourself gifted, but most really need the step by step approach. We ought not ask them to be deprived.
Substitution makes this even simpler: Since 5^6 = 5(5^5), simply substitute x for 5^5. That yields: (5x - x) /4 = 4x/4 = x, and since x = 5^5, the result of the entire calculation is 5^5.
For those of us who have not had math courses for many decades, though we all use math in some ways, I have enjoyed these videos. Slow for some of you, but I like that he takes us through the process and even explains some of the incorrect ways of figuring out the problem though initially, those ways may seem to make sense. My one complaint is that the speaking volume is too low.
I didn't bother to look at the answers or listen to the video; here's how I solved in less than five seconds. When looking at an all integers problem with division, first try to figure out if the answer can be an integer because if it works, things get so much easier. In this case, 5⁶ = 5*5⁵. So (5⁶ - 5⁵)/4 = (5*5⁵ - 5⁵)/4 = ((5-1) 5⁵)/4 = (4 * 5⁵)/4 = 5⁵. Of course, it might have been a false end, but these are usually easy to check.
Clever equation- I’m going to try to answer without watching- 5^6=5^5•5 so subtracting 5^5 from 5^6 will equal 5^5•4 and dividing that by 4 will leave 5^5
It's easy when you think about it in concrete terms. 5^6 is 5 times more then 5^5. Take away one of those 5 times and you are left with 4 of them, which leaves you with just one when you divide them by 4. And we know that has the same value as the one we took away, which was 5^5.
That is extremely simple as the if we note that 5^6 = 5x5^5 then we get (5 x 5^5 - 5^5)/4 = (4 x 5^5)/4 = 5^5. Took a few seconds, and can be easily done in your head.
should be "trivial" for anyone who has taken ANY math at the post-secondary level. why? because you need to understand algebra, and you need to be comfortable working with numbers.
(5^6 - 5^5)/4 = 5^5(5 - 1)/4 = 5^5(4)/4 = 5^5. Period! --- PhD in Math, 1979. Those who get it wrong simply don't know the modern rules. But the video is fun.
It seems to me that you have not used PEMDAS once you get to 5 to the 5th ( 5-1) as you should solve P, Parentheses prior to the 5 to the 5th. Leaving you with 5 to the 5th times 4.?? Also, how did you derive the five and the 1, in the (5-1)???
Factor 5^5 for the left part to get 5^5 ( 5 - 1 ) / 4 or 5^5 * 4 / 4 or 5 ^ 5. It took me 5 seconds to find the answer. You will not get many people interested if you loose that much time on such simple problems.
Sir, I am 60 years old and love math but have forgotten the basic operations to solving problems, haven't really had to do these in over 40 years, I appreciate your videos, lessons to get me back to what I once could do! Thanks
Same here. Same vintage 😀
You are correct. I am blocking channel as solutions are too long and drawn out.
5⁵
I know how you feel my friend I'm 61 I haven't done this kind of working years some of it I didn't do it All.. I went to high school in the seventies back then algebra was not a mandatory class I never had it
The same but a little bit more logical way:
5^6 = 5*(5^5)
5*(5^5) - 1*(5^5) / 4 = 4*(5^5) / 4 = 5^5
It's like 5 apples - 1 apple level math problem. :)
Exactly how I did it.
Yes, I see a picture and "notice" that (as you point out) 5^6 is 5 times bigger than 5^5 and transpose it to 5x - 1x over 4 = 1x or 5^5. I wondered if you "saw" that or "worked it out" if you see what I mean.
@@cliff481 I see this two ways simultaneously. As 5^6 and as 5*5*5*5*5*5.
So, I can not unsee the fact that 5^5 or 5*5*5*5*5 is part of 5^6 like 5*(5*5*5*5*5).
I hope it helped. :)
That's how I did it in my head in about 7 seconds.
If you use Apple(s), you are most likely not able to calculate this without a calculator. 😅
How to string out a 30 second problem for 15 minutes.
Yeah. Did it in my head in 30 sec
Yes in fact. I seee several videos of tenis guy AND always make the same.
Hey, a man's got to make a living
Thank god for the fast forward button
Good for you to have this easy! It isn’t a given to all!
Thank you for explaining several ways to do each problem and taking your time instead of rushing through.This is excellent for young children just learning and also for senior citizens that are brushing up on things that they haven’t done in years!Teaching math so that the student really “gets it” takes a special skill!Thank you!
And for senior citizens not only brushing- up but homeschooling their grandchildren.
@stompthedragon4010 yep. The way they're teaching in school now, I have to relearn so i can know how to help the grandkids.
The objective is not getting the correct answer.
Rather, it's about learning the concepts which may be applied to more difficult questions.
Some students are only interested in having the answer without any knowledge or understanding to resolve the problem.
Ok so I am 50 yrs old and math has never been my subject. But let me say in this one video I learned more than I have known all these years. Somehow you made it so easy for me to understand. Thanks.
Would have liked inclusion of the term “order of operations” which you have mentioned in other problems.
Another *excellent* point being made at 10:16 is "you have to consider who you're learning math from"! Kudos, @tabletclass 👍👍👍
I think that many/most of us are aware of the difference between being taught-by-rote versus being challenged to THINK.
With the-LATTER as teacher, one can often IDENTIFY one's weak spots WHILE RESOLVING them. Well... if one takes the time to do so... 🙂
I am glad you explain the problem in detail. Math is my weak spot. I can do it but been 20+ years since I took a College math class. ( I returned to college in my 50s) so had to start all over practically. NIW I enjoy these to keep my brain working.
Answer is E: 5^5, easiest to refactor the 5^6 into 5(5^5), then subtract the numerator which then yields 4(5^5)/4 which makes the answer 5^5.
your explanation is confusing to those who are not wizards in math.
Thank You! I appreciate that your teaching method is geared towards students learning this for the first time.
e) 5⁵
Factoring out 5⁵ yields 5⁵(5 - 1)/4 = 5⁵ × 4/4 = 5⁵ × 1 = 5⁵
yep
If you factor out 5^5 you get (5-1) in the parentheses which is 4. This cancels the denominator leaving 5^5.
So my problem is that all of your tangents made me lose my train of thought. It was worse at the end, did not make sense.
Takes too long futzing with WRONG ways to solve. Needs to get to the point abd just show hiw to SOLVE IT.
OCD
GOOD & thank you!😁😁 At 1:22 a definition of "multiple choice" is stated: "1 of these is the correct answer". This means *exactly 1* correct answer, ie no less than 1 correct answer & no more than 1 correct answer. One can validly *DEDUCE* from it that "all answers except 1 are NOT correct".
Then there is the D answer that is A & C are correct. Just not usually in math,
17
A) is odd
B) is even
C) is prime
D) both A and C
D is most right but the others are STILL correct so your hypothesis is absolutely wrong since only B can be eliminated. I assume you do not do well in tests.
@@toriless "you do not do well in tests" is not a correct assumption.
If you do not really appreciate this teacher’s work, why do you waste your time here, criticizing and badmouthing?
Please know that there are people who appreciate Mr John’s teaching and let them benefit from his work.
Tip..... If you want to help anyone in maths.....1. Get to the Point , 2. Get to the Point , 3. Get to the Point!!!
Stretching a 1 minute session for 15 mins or more would take people many years to get past junior grade at that rate !!!!! Most people including myself would much prefer a direct simple approach rather than take a walk around the garden to see what's there!!!
You're not helping anyone stringing them along like you are!!!
He's trying to give reassurance and encouragement to those unsure of how to proceed. Those (me and I'm sure thee!) who can see what to do at a glance, don't need this. We already have a justified confidence! Not all have that luxury/accomplishment.
@@davidwright8432 Reassurance, encouragement and even build confidence in people, these are all good, but stretching it out like this does not, build confidence, reassure or even encourage, when lessons are dragged out like this...... Dragging them out like this, lessons are more likely to instill impatience and frustration by.... Not Getting To The Point In A Timely Manner !!!
I'm with you. Get to the point quickly. The advantage of YT is that you can rewatch any video you had trouble understanding.
OK, *you* are allowed to use a calculator. In another room. Off campus.
Love your videos! You explain things so well. And your voice is very calming. 👍
I left school in 1969. I did maths in several engineering coursed up to Honours degree level over many years. I still find your explanations thorough and interesting. I could solve this problem easily, most engineers could, but undoubtedly most of us engineers, especially those, like me in their eight decade, likely would use a calculator. Funny that considering that calculators did not exist when I was at school.
I am sure I would have been taught how to factorise the equation at school but I didn't remember it and I enjoyed being reminded.
You actually have to learn the rules. You cannot do math without really knowing the rules.
This video (15+ minutes) is way way too long for the problem. The majority of the of the time has nothing to do with how to solve the problem. If you're watching these videos to help improve your SAT or ACT scores you'll never get there.
Very boringexplanation
except when n = 0, sure got tired of that caveat in algebra
Fun to work - bring back old memories of strugging in math classes many years ago. Thanks for the problems.
Love these videos, but you really need to raise the volume somehow!
If you want to find the difference between x^n and x^(n-1), it's always x^(n-1)*(x-1). In this case, 5^6-5^5=(5^5)*4. The answer is 5^5
(5^6 - 5^5) / 4
It is very tempting to just say 5/4 but 'to the power of' doesn't work like that.
So .. let's express 5^6 as 5^5 x 5 so that they are both 5^5
((5^5 x 5) - 5^5) / 4
which is also
(5^5 x 5) - (5^5 x 1)) / 4
which can be changed to
5^5 x (5 - 1) / 4
5^5 x 4 / 4
and 4 / 4 = 1
giving us 5^5 as the answer.
"It is very tempting to just say..." is the kind of sentence which means you have no idea what mathematics is about.
@@frenchimp It's interesting you should say that .. because my mathmatics teacher at school (back in the 70s) always used to say ''Now, it's very tempting to just say'' before going on to explain why something was wrong, and in this case I was just pointing out one of the things that people could get wrong before going on to answer the question.
If you think that means that I ''have no idea what mathmatics is about'' then I won't do it again .. however, after 50 years, it may be too late to tell him.
This was helpful. Thank you.
I put it in a calculator. Gives a actual 5^5 value 3,125 This is why this stuff is way super confusing to many. It doesn't answer as "5^5" . Many fail to see the need for such mental gymnastics
E baby
Dude, you RAMBLE ON! Get the hell to it already!
Is someone forcing you to watch this video?
@@jeffwells641 No. Sadly I stumbled on it and mistakenly thought it would be entertaining. It’s too hard to watch with all the bullshit drawings and windy commentary. I wont waste any further time with these vids.
You know you have control of the video. Stop complaining and skip forward like I did. You are just ignorant and not a victim.
@@michaeld2662please make sure not to stumble hereafter, because your badmouthing our teacher, does not help us, who really appreciate his work.
Life is too short and we have to find ways to live respecting each other in harmony.
I reckon the answer is f) = 3,125. Derived from: 15,625 minus 3,125 equals 12,500 divided by 4 equals 3,125. Simple!
If it's not acceptable to the OP, somebody wants you to follow some rule that makes sense only to the person arriving at the alternative solution, and to the people who also follow that rule. There are plenty of similar maths puzzles online where people differ owing to their following different rules. Maths is NOT a black and white discipline, where there is only one correct solution for each problem. If you want to do well in maths class, learn what rules that particular teacher wants you to follow.
lol 3125 is 5^5 so (e)
Still the slow way, easy but slower.
@@phildavenport4150: Since 3125 IS 5**5, what the hell are you babbling about? It's NOT a different solution than all the comments using algebra, factoring out 5**5, and getting 5**5 as the answer. It's just doing the problem directly with good old basic pre-algebra arithmetic, like we did in middle school, 50 years ago.
This is how I did it too. But the 3125 breaks down to 5^5 so that’s the answer I committed to. Which appears to be correct but this method seems to be incorrect?
As an engineer, I work with several people who didn't pay attention in math classes, but were somehow promoted to the next grade anyway. They think I'm some sort of math god because I can solve problems like this in less than a minute.
Yeah, when I transferred schools for 9th grade they had me take the PSAT with the 11th and 12th graders. I did not know about the minus 40 or I would have had a 790 since I answered them all, as it was my lousy 760 beat everyone but 1 chicken senior who skipped a few questions. They let me take the advanced algebra after those results.
I got it by making a chart of 5 to the 1st through 5 to the 6th. Then i just did the simple arithmetic. I couldn't remember how to work with exponents, but that worked and didn't take too long.
It is quick, take half a minute out of a huge test. I know, I typed them out in a response.
Here's what I did:
5^2 = 25, 25 × 25 = 625 (4th power), 625 x 25 = 15,625 (6th power).
15,625 - 3,125 (ans/5) = 12,500
Now that we know the top answer is 12,500, divide it by 4, you get 3,125 which, surprise, is the 5^5 answer we had earlier.
Fantastic. It is the harder way to do it but YOU got is right. Take that A+ proudly!
I do wish you can be a little less long winded.
Agree. Even taking into account explaining the how & why, this could have been an 8 or 10-minute video instead of 15.
He is trying to help others not good in math, I just skip forward a lot, ask TH-cam. I am sure they notice it.
It might not always be the right answer for solving math problems, but if I don't know right away what to do I will typically factor the numerator first then the denominator and see if it simplfiies the equation or allows for cross cancelling.
@proteus404 - and still struggling today?
(5^6-5^5)/4=
5^5(5-1)/4=5^5
Correct!
The 'formula' 5^5 (5 - 1)/4 does the trick. Nice job, John.
3,125 was the answer I came up with while doing this calculation in my head. I was correct. Although, this answer of 3,125 is not an option in the video. The video shows the answer is 5^5. This is correct. However, 5^5=3,125. So, the ultimate answer should be 3,125.
They wanted you to apply the logic he demonstrated rather than plugging away at the math, I agree it does not take much longer but the question is testing n=your ability to for application not how fast you can multiple. I was working it out and pause when I saw (5-1) / 4 which equals 1. I did the multiplication in my head and then saw this relationship which you missed.
Both are correct but only 5^5 was given as a possible answer.
The problem is you were possibly taught that on the other side of an equal sign is supposed to be an 'answer'. That is false. On the opposite side of any equal sign is EQUAL WEIGHT. It can be expressed as simply, or as complex as you would like. If the equal weight is supposed to be in a particular context, it is so stated in the question/problem. What if the multiple choice contained BOTH 3,125 and 5^5? Then clarification about what form the weight was required to be in would be needed. In this case, 3,125 was not an option, so 5^5 was the only valid equal weight.
You say that 5^5 = 3,125 - which is true. Then you say that the answer should be the right side weight (3,125).
Well, an equal sign works both ways (because ultimately it is a BALANCE point), so..
3,125 = 5^5. According to your logic of where we obtain 'the answer', now your answer should be 5^5.
The 'answer' is not in the equation, it is within the multiple choice selections.
@@michaelzoran that assumes the author didn't screw up. These internet posting are often done by people who cannot solve their own posts. I admit that I only looked at the correct response without evaluating it as it fails as an identity though it works for these specific answer. My answer turned out wrong and that is notbthe end of the universe.
I wish I had a Algebra teacher in JH like you, I failed. Come in college I had great teachers and did great but the things we worked on a Calculator wouldn't help you any(this was the 80's) unless you knew how to work the problem. Most of the "what is the correct answer" you see on TH-cam are not formatted correctly so they create a argument, Mathgirl did a great video years ago covering this..
I never really understood math. My teachers only taught one way and I never was successful. As a Senior, I guess time has run out for me.
This dude would take 100 years to teach you Grade 3 math...
Yeah - He's pretty long-winded.
@@colt4667Pretty? Very!
Amen 🙏 much too much….DRAMA!
He's the reason we have self-checkout.
Good to digress and go on about a buntch of fluff.
When you have the division line , I was always taught the numerator and denominator were in separate parenthesis. IE 3+4 over 4*3 is (3+4)/(4*3)
It is best practice, especially with computers.
Fast forward 12 minutes to avoid endless waffle.
He just goes on and on and on and on.......
Zzzzzzzzzzz...lim 0 -> inf.
That is why fast forward is made available.
My answer is 5 to the fifth power. The numerator can be considered as 5 to the fifth times (5 - 1) ; that is 5 to the fifth times 4, and as the denominator is also 4, the fours cancel. leaving 5 to the fifth.
My goodness I must have been well taught all those years ago, it just comes flooding back….great mind stimulation.
At first I didn't remember the process either until he started into it, then I was like... Well Duh!!.
@@chrish7336 I managed it in my head then checked if I was right.
E. Factor out 5 to fifth power. Leaves (5-1 ), which is 4. 4 innumerator cancels out four in the denominator, leaving 5 to fifth power
15 MINUTES i'LL NEVER GET BACK.
I skipped forward, you know TH-cam has a little control on the bottom. You seem to know nothing about how to use TH-cam. Maybe that tutorial should be next on your list.
Did you get the answer correct right away? If not it’s your fault for watching that long.
@@FoodNerds If he got it right immediately and he knew it was right, you're right, it is his fault to "waste his time". I think he needed to make sure his method was correct in attaining his answer.
I know you said "No Calculator" John, but I had to see how my phone's cheapo calculator would deal wit this. Even when putting parentheses around the exponents, it gave incorrect answers. I had to use EQUAL sign before dividing by 4 to get it right.
I'm an old fan of RPN logic, on the HP with an ENTER key but no = key. I never get wrong answers with my HP 41C. But I've never found a phone with RPN in the calculator program.
Tricked me. I fell for the 5/4.
Learn so much from your videos
Thanks for doing this .
What would you say is the ratio of grateful people to ungrateful ?
Just a rough estimate
I really want to know. ❤
why is your volume so low?
I thought it was me. I'm hard of hearing as it is. Tried to headphones.
@kelleeb Indeed! I left him a message as well.
What? It is really high.
@@truthcooperator4683 It really isn't, lol. Maybe your headphones are highly sensitive, but at 100% with mine, I barely hear a whisper on this video.
same for me
Did this in my head in less than 30 seconds using the long way, got 3125 so picked E … Would have used your method if it wasn’t a simple number like 5’s … 5’s are too easy to do in your head! … In my head I multiplied by 10 then divided by 2 …. 5*5 =25 250/2 = 125, 1250/2=625, 6250/2=3125, 31250/2=15625 …. Took the 3125away from the 15625 easily in my head to get 12500 then just halved it twice 6250 then 3125 which was the 5th of my 5’s so got 5to 5th in under a minute with no writing down … does this make me weird? Doubling and halving is too easy … even the subtraction was easy … so I chose the easiest option.
Way to long winded .... just get on with it.
Getting on with it doesn't make him any money. TH-cam videos need to get past certain duration limits for monetization.
How do you know he spends this much time in an actual class, unless you have been in one of his classes.
An object lesson in how to take something fundamentally interesting and make it really, really boring!
Yes, quicker helps.
The answer is E. 5^6 = 5 * 5^5 = 5^5 + 5^5 + 5^5 + 5^5 + 5^5. If you subtract 5^5 from that, you stil have 4 of them. divide that by 4 and you get 5^5.
I used a calculator cause my brain doesn’t brain real well sometimes and I got 3125, which turned out to be A correct answer, but not the answer your looking for. It’s the same as Hello is to G’Day is to Hi, different words, same intent.
5 25 125 625 3125, 15625, it is easy to do without a machine.
i am now retired, it’s good to see these problems again. though i have to say, throughout the years, i never had to solve nor ever came across a problem that i had to use this operation. i still can’t think when i’d be using it.
Audio was to low to hear anything.
yeah, I kept thinking of the scene in Blazing Saddles when the teacher was speaking too softly and everyone complained and then she started yelling.
Same.
Spelling was too wrong to understand.
It’s funny how I know how to use all of these stuff but I just don’t know if I need to apply it in a certain situation
Absolutely guess at answers if you don"t kno and if wrong answers aren't penalized. Then there's the quick screen to throw out obviously wrong answers to improve probabilities.. AND Always attack problems you KNOW how to do and then go back after those you aren't sure. Never waste time on something that confuses you until.AFTER you've answered easy-to-you questions.
Please do this for me 🙏
Kate likes to walk down moving escalators and she takes one step at a time. When she walks down at a rate of 2 steps per second, she reaches the bottom from the top after 18 steps. When she is exhausted, she will walk down at a rate of 1 step per second and she will reach the bottom from the top after 12 steps. Find the time- taken for her to reach the bottom from the top if she just stands on the escalator.
Depends which way the escalator was moving but maybe forever.
Take out a multiplier of 5^5 from the top and it falls into place easily.
not correct way
@@majorrgeekoh yes it is. that IS the way.
@@matswessling6600 - you cannot subtract a multiple - the correct way is to follow BODMAS and you never go wrong
@@majorrgeek noone said subtract. "take out" here means "factor out".
as in 5^5(5-1)/4.
@@matswessling6600 - then next time say "factor out" instead of take out
Well, 5^5 is (5^3)^2 = 125^2 which is going to be up around 15,000. 5^5 will be a fifth of that, or around 3000, subtracting it brings us down to 12000-ish. Divide by 4 gets us to 3000-ish. 5^4 is 25^2 = 625, so the only answer here remotly big enough is e, 5^5. It took me a lot longer to type than than to think it - I probably went through it all in 6-7 seconds.
Way too longwinded. I just looked at the answers given by the commenters.
Seriously … wayyyy too much irrelevant drawing and blabber.
Good work, but needs improvement. People’s time is valuable.
I never understood powers math and after watching this 5 times I’m still confused. Would you make one that only goes through the solution the correct way? I’m 70 & have never had to deal with powers except in math classes. That said, I’d really like to know how to do it. I vaguely recall a math teacher saying something like add the exponents together. I just don’t remember why.
5 to the power of 5 is the correct answer.
I got the answer e) 5⁵ by taking out the common factor of 5⁵, but it's hard to get your head around the fact that the difference between 5⁶ and 5⁵, is 5⁵ multiplied by 4.
It takes about 5 seconds in your head. How does he make this into a quarter hour video? I watched the first three minutes and jumped.
I skipped, watched, skipped, watched, I would recommend that for all his videos but some people need the rest.
Those of us who are natural mathematicians will always fast forward John's videos. Consider yourself gifted, but most really need the step by step approach. We ought not ask them to be deprived.
Substitution makes this even simpler: Since 5^6 = 5(5^5), simply substitute x for 5^5.
That yields: (5x - x) /4 = 4x/4 = x, and since x = 5^5, the result of the entire calculation is 5^5.
great explaination. factor and solve. thanks for the fun.
Yes it was
For those of us who have not had math courses for many decades, though we all use math in some ways, I have enjoyed these videos. Slow for some of you, but I like that he takes us through the process and even explains some of the incorrect ways of figuring out the problem though initially, those ways may seem to make sense. My one complaint is that the speaking volume is too low.
I just skip forward a lot. Better than the bitching some do.
Such muttering, cannot hear, even with volume on high...
(5 to the 6th) - (5 to the 5th) = 5 * (5 to the 5th) - (5 to the 5th) = 4 * (5 to the 5th). Dividing that by 4 gives 5 to the 5th or (e).
Too much talk. I started to sleep.
The detail explanations are important to allow the mind to fully absorb the solution subconsciously.
I didn't bother to look at the answers or listen to the video; here's how I solved in less than five seconds. When looking at an all integers problem with division, first try to figure out if the answer can be an integer because if it works, things get so much easier. In this case, 5⁶ = 5*5⁵. So (5⁶ - 5⁵)/4 = (5*5⁵ - 5⁵)/4 = ((5-1) 5⁵)/4 = (4 * 5⁵)/4 = 5⁵. Of course, it might have been a false end, but these are usually easy to check.
It’s not what you do,it’s how you do it.
There are Rules to follow.
I got it, and it took just a couple of minutes. But I'll have to watch and figure out why.
The answer is 1.25
Nice trick with the 9 of any base.
(a^n - a^(n-1))/(a-1) = a^(n-1)
Appreciate your channel. Great to catch up on my math which I always made it harder to understand. ❤️
It’s only easy if you understand this. I have worked with kids who have major learning problem.
I’m thankful for these videos.
So, if we have: x^6-x^5/(x-1), we look for GCF, and make it: x^5(x-1)/(x-1). Then we cancel out (x-1) and arrive at x^5
Meant to write: John, could you please turn up your volume. Thanks!
Take 5 to the power 5 as common then you will have (5-1) over 4 which is 4÷4= 1. Hence the answer is (e) which is 5 to the power of5
Factor out 5^5 up top and it becomes (5^5)*((5^1)-1) = (5^5)*4
Divide by 4 = 5^5. Done. Saved you 15 mins
Clever equation- I’m going to try to answer without watching- 5^6=5^5•5 so subtracting 5^5 from 5^6 will equal 5^5•4 and dividing that by 4 will leave 5^5
Factor out 5^5 and you’re left with 5^5(5-1)/4. 5-1 is 4 divided by 4 is 1 leaving 5^5
He speaks in prosody. Monotone is a vocal utterance that is a single tone without variation in pitch or harmony
It's easy when you think about it in concrete terms. 5^6 is 5 times more then 5^5. Take away one of those 5 times and you are left with 4 of them, which leaves you with just one when you divide them by 4. And we know that has the same value as the one we took away, which was 5^5.
Same idea, just backwards
This took me all of 4 seconds to solve in my head. Thanks for the 15 min video
That is extremely simple as the if we note that 5^6 = 5x5^5 then we get (5 x 5^5 - 5^5)/4 = (4 x 5^5)/4 = 5^5. Took a few seconds, and can be easily done in your head.
should be "trivial" for anyone who has taken ANY math at the post-secondary level.
why? because you need to understand algebra, and you need to be comfortable working with numbers.
Starts at 6min50
Mental arithmetic in 3 seconds. Numerator = 5^5 (4). Hence e).
(5^6 - 5^5)/4 = 5^5(5 - 1)/4 = 5^5(4)/4 = 5^5. Period! --- PhD in Math, 1979. Those who get it wrong simply don't know the modern rules. But the video is fun.
It seems to me that you have not used PEMDAS once you get to 5 to the 5th ( 5-1) as you should solve P, Parentheses prior to the 5 to the 5th. Leaving you with 5 to the 5th times 4.?? Also, how did you derive the five and the 1, in the (5-1)???
top is 5^5(5-1)=5^5x4 so answer is 5^5 aka answer choice e.
Excellent explanation!
It seems it could be generalised as:
(n^m - n^(m-1))/(n - 1) = n^(m - 1)
....
n^m = n * n^(m-1)
Therefore
n^m - n^(m - 1)
= (n * n^(m - 1)) - (1 * n^(m - 1))
= (n - 1) * n^(m - 1)
Divide both sides by (n - 1):
(n^m - n^(m - 1))/(n - 1)
= ((n-1)/(n-1) * n^(m-1)
= n^(m - 1)
Sorry, typing on my phone is harder than I thought it would be. It might be clearer to write it out by hand in more standard notation.
answer is B
5’’’’. You make it very interesting , thanks
Factor 5^5 for the left part to get 5^5 ( 5 - 1 ) / 4 or 5^5 * 4 / 4 or 5 ^ 5. It took me 5 seconds to find the answer. You will not get many people interested if you loose that much time on such simple problems.
Pull out 5^5 out of the bracket. It becomes 5^5*(5-1)/4 so it resolves to 5^5
Yes. Took me about 10 seconds
That is what he did, watch again
@@toriless I didn't even watch it a first time lol
15 minutes is too long for me. Too much irrelevant info.
76 yrs old and realize that math is the one thing that will make your brain young.!!!
why did you add the powers of 5 to the 5th and 5 but did not add 5 to the 5th and 1? does that mean 1 does not have an assumed power?