Solving a proportion with an unknown variable (example) | 7th grade | Khan Academy
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- เผยแพร่เมื่อ 14 ก.ค. 2011
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Here's a great video where we explain the reasoning behind solving proportions. We'll put some algebra to work to get our answers, too.
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ill make things easier
8 10
--- ---
36 n
36x10=360
360 divided by 8 = 45
easy
Thank u
Thanks
Thanks dude
realy thanks
Omg thanks this helps and easy❤️
i wonder how this guy is doing. he's always been one of my favorite narrators. man..
Math is literally making me have a break down
Same bro
Facts bro I can’t even do Proportions
Same bro it's making me go crazy out of nowhere
real
Who else is the sad sad 11th grader watching this video for ACT practice because you're almost an adult and you still cant do proportions
Thanks khan you got me through another problem thanks i finally going to get my degree im in the early stages of it but with your help im going to get this finally thanks for this math upload
J-Hope's #1 😂😂😂😂💔
What happened? How did it go? :)
6 years later did you get your degree
Thanks so much khan academy I have been trying to do this for hours thanks again!
how in the world do you get these numbers
I wish someone told me that in these words when i was a kid. I did it mechanically without real understanding for years of primary school.
Thanks man
For people that are confused, there is an easier way, just multiply 36 times 10 then divide by 8. the answer will still be 45
thx
Thank you
No you can't because sometimes that won't always work.
That's what my Math teacher say. Btw, thx
Sammy Sen wdym
Thanks. This is very helpful
Ya
I wish math was still like this
thx for the new ways of solving proportions with an unknown variable.
thanks! Helped a lot!
Thanks you for these videos. They are so helpful.
@Evelyn Reyes that means you didn't understood it??
u helped me so much tysm!!!
I'm learning this in sixth grade.
Katrina me to and I have my final exam tomorrow and I can’t figure this out. Ughhhhhhhh
I'm learning it in fourth grade!
@@abcxyz6247 oof poor you
Life saver!!
math is so hard but with khan academy its got a lot more easy then i thought.
his the best for kid in school
Was anyone else taught to just flip right side
multiply straight across and solve for the variable?
8 10 8 n
--- = --- --- x ---
36 n 36 10
8n = 360 n = 45
of course you can do cross reduction by common
factor to get 4 n
--- x ---
36 5
4n = 180 n = 45
but either way, flipping the right side
multiplying straight across and solving for variable
is by far the fastest method to the answer.
It makes sense but he makes it more complicated. The simplest way would be just to make a simple algebra equation 36x10=8n and solve for n. The way he's explaining it shows the logic behind it instead of just a formula. You are finding a number to multiply the numerator of the first fraction to match the one on the second. Then simply multiplying the denominator would give you the value of the second denominator. He makes it sound more complicated.
This is... Interesting
Nice. I love mathematics))
Im in gift math but got a 70 d, on this, i actually think gifted children is actually for special ed kids who teachers just want them to feel better
wow i got it thank you
What about cross multiplication?
Just cross multiply then divide the number by the variable.
already knew that
I really don't get this guy, this is super complicated.
+nonyobizness you literally just do cross multiply and use algebra, do 8 x n so that would be 8n, and do 10 x 36 = 360 so 8n=360 so divide 360 by 8, n=45
+City 5 made that sound so easy you just broke it down for me so easily thx
+City 5 I didn't get far in the vid yet but it is very complicated
Thank you! I have a final exam coming up and this literally saved me from a headache.
@@city5478 omg this is more helpful thanks
How on earth did people find this helpful????
Exactly how do ppl get this mess
What do u find confusing. It confused me at first but its actually kinda easy now
@@medhasarker6967 i didn't learn this from khan academy but in the other channel
@@jakesucgang4497 ohhhh okiii
khan academy helped me like 90% of math but if they dont have practice it's just like 5% but atleast its free
Sal Khan be like, you do that, then that, and that’s the answer. 🤯🤯🤯
It says that this is 7th grade math but im in 6th learning this...weird 😑
samee
i’m in 10th grade learning this 😭😭😭
Im just grade 6 and we are talking about proportions 🤪🤪🤪
i get it
What?
I need solve for the unknown!!!!
🤣🤣🤣🤣🤣
Well this was a while back, your probably in collage now haha
What if you get a remainder while doing cross products?
How’s collage going
are u still alive?
@@nicv2 yes, unfortunately
???????
thx
What if the cross mutiplying result have the coeficcient as the numerator?for example we have 4/x=5/10 and the result of cross mutiplying is 5x/40?do we flip the 4/x and 5/10 so it looks like this?: x/4=10/5?
is anyone here from 2020?
Nora Madih hi
Yep
Yep
No
lol
A have a maths exam in this 3 week so is there any practice to do.
Its been 3 weeks good luck
@@yenasone thanks dear
Man is speaking enchantment table
U save my life
Cross multiplication is the last method I use when multiplying fractions
cross multiply carl...
still didn't get it :(
What part did you not get ?
Zciwaraful I’ll check this in most probably a year to see whether he replied or not
It’s been 6 years they haven’t came back to this video since 2014
Do u get it now
Yes, I did. I'm in college now taking calculus, because I'm majoring in Computer Science. I can't believe I didn't understand this problem 😂
8/36 =10/n
8n = 36×10
n = (36×10)/8
n =360/8
n = 45
Nashwa Shalaby ty
My teacher does cross multiply
nope still dont get it
Lol
Yo yo yo
i still dont get it :(
Arend Verfaillie You need any help? I can try and help.
Your comment is 2 years old
xD No one helped him :(
this is sad
im being foreced against my will to watch this video by the brain dissease called:school
Same 😂😂😂 he makes it so complicated
i hope you get well it takes a journey of homework for freaking 3 months straight.
Could u just do 8•n=36•10?
in a ratio, it's suppose to be like this,: 8:36=10:n
Khan acadamy has more videos
What if theres a variable on side ? Ex :-23 = -12/5 m ☆☆☆
FAST ANSWERS PLZ!A
Ruby Rose
Work with it as if the negative isn't there and then add the negative to final answer
I agree to complicated 😅
I'm confused
does anyone else hear those strange noises in the video?? All throughout the video there's breathy sounds and I'm not sure if its just me
Midterms tomorrow
i dont understand anything, i need help
@Depressed Patato Yup 🤩🤩🤩
i keen they are not math
Why isn't it protocol to always reduce fractions first? Even when cross multiplying; n= 90/2 is easier then n= 360/8
@Elizabeth Scheuermann Very insightful... Clearly not what I'm asking.
I find it easier to add then divide... Does that mean I can add before dividing?
ooohhhh...
I still don't get it
@@KGF-bw3wm shut up plz... thank you
@@KGF-bw3wm oh u were just "bored"?
@khan, I need proportions + variables, using similar shapes. Please put a video up showing this and proportion video together.
isn't this 6th grade (NY standards)
Isaac Cheong Kinda true even though I am Canadian.
I was 8th grade when I learned this. Maybe I just suck at math. (No dip but still)
TSM TEAM
Just cross multiply then divide the number by the variable
Coeficcient***
Coeficcient***
This video makes no sense idk how ppl get then mess
Anasia Echavarria nah he’s just correct
JUST WATCH THE VIDEO
This was probably the most confusing explanation. I am more lost than when I started.
Snoc snoc snoc snoc snoc
great mic quality ign 1/10
Math
they bare not math
I dont understand
Check the basic videos first
..now what was that
I've finally found The Kim Taehyung oop
This is too Confusing
no its not!
Hii
Uhm my yeacher taught us an eazier way ima just go an do that so yea bai😉
He's doing a fantastic job, if you don't understand perhaps you should go back in the series until you do.
i thought this was a pewdiepie video.....
He made this horribly complicated for no reason. Just cross multiply.
who solved the whole thing in 5 seconds using cross multiplication
you
Me
I know
sooo
learn to teach
QuarterKill at least he is better than you if you teach
You first.
QuarterKill Learn to repeat the video until you get it.
I'm doing this in 6th
Me too in spirit of math live in Canada
same here
i came to this for a little bit of help and while i was listening i solved it a whole different way with TWO STEPS and it took him almost 7 steps because they do too many unnecessary steps that are WAY too confusing and arent helpful AT ALL!!!
they are just trying to break it down to make it easier for us to solve!
bruh, it was way easier to input torpedo data into a TDC than this
SUCC SUCC SUCC SUCC SUCC SUCC SUCC SUCC SUCC SUCC SUCC SUCC SUCC SUCC SUCC SUKK SUKK
Lol
i donated 1 dollar
This confused the hell out of me.
I hate math
Learn how to teach your doing like 5 different ways at the same time
DS Han preach
DS HANS I AGREE HE NEEDS TO SHUT UP
Why do you keep calling everyone dumb
i hate math
i don't like khan academy its just gibberish he is a terrible teacher
Tosh Is it like you could do better?
Tosh *COUGH COUGH KHAN IS PARTNERED WITH NASA*
not helpful at all
this makes zero sense
Horrible video