Understanding division of fractions | Fractions | Pre-Algebra | Khan Academy
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- Опубліковано 10 сер 2015
- Using a number line, we'll explain the rule of "invert and multiply" when dividing two fractions.
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![[柴犬ASMR]曼玉Manyu&小白Bai 毛发护理Spa asmr](http://i.ytimg.com/vi/0TsXQ7z2Dh4/mqdefault.jpg)
I was in 4th grade when i learned this and now im in 7th and I finally understand.
How time passes by
SAME LMAO
same..
nah im halfway through tenth grade rn and im still struggling 😭😭
Its a full circle of life.......!!!!!!!!!!!!!
I kinda love watching Khan academy 👍👍 thank u for helping me Everytime that I don't know the process
I was in 4th grade when i learned it and know im in university this is one of the most important things im taking in my engineering design so if u want to be an engineer u need to understand this pretty well so good luck for anyone who is learning this
This dose not help
Busy I’m
I used to hate u in 3rd grade because I didn't get what ur saying but now I'm in 7th and I finally get what ur saying
Akela siders same thooougghhh ayeeeeee weee bottth in 7thh grade
Funny me too
but im in high school lol hahah your funny
I’m in 6th grade but I’m in ace math so
Akela siders you're now 9th grade right
@@fade3664 I literally am up at midnight trying to figure this out so I Dont fail a test and get a zero in math. I wish I was you.
Time for me to question reality all over again just because I can't understand one simple video
lol my mom said i might need a tutor
Yea I can’t either
Brain is hurting
I think i had a headache already
Brain hurts
Is equal to... is equal to... is equal to
Error 404 answer.dll not found
ZA WARUDO
@@kawakiuchiha1506 lmao
I still don't understand but overall great explaining!
your other videos have been helpful
much appreciated!
why do people dislike this? is free education not enough for you?
Because they aren't successful in life
omgawesomeomg to
omgawesomeomg probably because they didn't understand his explanation
There are various reasons such as: Mathematical jargon terminology; reasons behind a particular formula; speed of working out etc. So please be very understanding as Maths is NOT an easy thing to grasp!
omgawesomeomg maybe this is easier to under stand than at school
I really love this video. Thank you Sir
Hello past person
Thank you so much! I have a test on this today and you helped
me: *sees math*
my brain:*brain.exe stopped working
Thank you Khan Academy! 😊
Yep! I’m in 5th grade preparing for 6th because my teacher is acting like I’m not in the class (I’m full virtual) so my mom wanted me to watch these, I think 6th grade is gonna be a breeze, I learned this in 3rd grade!
@@wemble6117 I’m in 6th grade now
His obsession with different colors for each number is really getting to me. Takes so much more time and patience, for zero return...
I already feel bad for saying that, I have so much love for this man and he has helped me so much! This is the only thing that I dislike about his videos.... and thats not an awful lot to complain about..
He does this because he wants to show a way that it's easy to see the numbers. And, you DO NOT get zero in return! This guy is trying to help you sucseed in math, bro!
@[R] YES 😂😭💀
My teacher calls those jumps rainbows~
I think you just saved me from failing my high-school entry test. T h a n k y o u. I could never thank you enough.
I learned this like 5 years ago got a question with this forgot how to do it and was shocked it worked you saved me from failing algebra 2
This is such a good vid for my finals
Not only on your finals also on your homework if u have a homework/assignment
@@izharpagayon5826 Exactly
I learned it 4 years ago, and I finally understand it now!!!!
It works for me. In fact the doctor who treats me for the accident that caused damage to the left side of my brain said it works because of imagery, which comes from a different part of the brain being connected back to the part that was hurt. He still doesn't know how exactly it's working but it is. Without the imagery I would never remember the numbers.
thank you so muck you are changing lives ,sharing your math you helped me a lot when i had to do my big test of division fractions. thank you so much:)
I don't get it how dus dis dude actually make a living off doing fractions
Maybe the billions of views they get
@Kaislyn Snyder they have an app too
@Kaislyn Snyder Stfu I said that 7 months ago xd
@Kaislyn Snyder mans getting mad just saying Htf he do his job and pay rent
I really like it and just highly recommend and practically appreciate it❤️
...Thank u sir❤️✨
I learned this stuff years ago but I like rewatching easy videos because I like his voice 😂
omg same! makes me feel very comfortable
@@LarkspurLight yay a fellow pony fan ^^ I like these videos a lot too! ^w^
@@nv16123 woohoo! mlp rules!
@@LarkspurLight yay it sure does! ^w^
Try the KFC Method
1. Keep the first fraction
2. Flip the second fraction
3. Change the operation to multiplication.
THIS THING MADE ME HUNGRY
Yep!!
It’s actually KCF
1. Keep the first fraction.
2. Change the operation to multiplication
3. Flip the second fraction
No hate tho. 😊
I thought it meant, Kentucky Fried Chicken 🍗
KCF but it’s all good
Iman Mohammad yup
Help so much thank you
Great hesi test math test refresher!!!
Am learning this in 5th grade am about to go in six grade thank you🎉🎉🎉🎉🎉😊😊😊😊
Thank you so much!! Now I finally know exactly why it works
Thank you so much, this really helped me on this topic of fractions. #LuvKhanAcademy
Don’t really understand. Can u explain in more detail? Thx
I was in zoom for almost an hour and didn’t get it I finally get it now and this video is only 5 mins
Thanks Mr Khan this helps a lot.
That HP tune-up notification at 3:30 steals the show this video 😁
great. i have never really knowed what is going on behind the scenes :) !!
HELPED me :)
I've been going through the Arithmetic course on Khan Academy but I've hit a wall here even with the explanation. I don't know why I can't grasp this, it sounds simple but my brain just won't make sense of it.
Khan helps so much thanks!
This is great thanks!!
I'm doing this during a six hour study session though I'm in fifth grade
Thanks for the refresher!
Great teacher!
These color make it easier to see and understand
Just saved all my grades :)
Hey I love you teaching I would rather have you as my teacher then an youtube that teaches
I learned this a while ago but i forgot it now but ty i have a test in a hour and i didnt study over the 3 days for even 2 mins
Better then anything I have seen
I like the way he teaches
One saying that I learned from my 6th grade math teacher when dividing fractions is "Keep, change, flip"
thanks it is was very helpful
Best teacher ever👍👍👍
Sir how did you add this hand tool in recording lecture. I shall be very thank full if you help me out to get this
How would you plot 8/3 divided by 7/8 on your number line?
8
_
3 I tried
You might need to add more numbers 7 over 8 so mark every 10th until you have 7, 8ths
10 20 30 40 50 60 70 80 90 100 (1) and do that
@@izharpagayon5826
8
--
3 me too
Hello past human being
Thanks really helpful keep up the great work
Thank u Khan academy 🤗🤗🤗
You teach me better than my teacher
Bruh about to take my geometry exams and I just know the little stuff like this is going to get me
Thank you
I am tutoring a boy in grade 8 who understands the mechanics of multiplying and dividing fractions. However, when it comes to creating an equation from a word problem he has difficulty determining which operation to use. Many adults would as well. Take this simple one: A water tank holds 80 liters. When half of the water is used, how much water is left? (Divide by one half, right? NO!) How do I explain the difference between dividing IN half and dividing BY a half (one half)?
show an example of both of these features
1/2 x 3 = 1/2 * 1/2 * 1/2 in short its 3 1/2s. ask him to draw multiple wholes and cut/ shade every one of them to represent half of that number.
3:41 that is what i think about khan academy the jumps are hearts
Your awesome thank you so much
Tthis makes so much sence now!
This* sense*
sooooo KNOW I get it!!!
what do u use to draw is my question..
this is a good video
There supposed to be a whole besides 1/3
Thanks u khan academy:p
Wouldn't it be less confusing if you just said " how many times does 1/3 fit into 8/3" instead of saying "jumps" it fits in 8 times.
ikr
Great video, but what if the denominaters are different numbers??
You need to make the fractions equivalent. You do this by finding the Least Common Multiple (LCM).
Yes, that is right, but the risult is not 4 units. So if we add to this result 3 then the result shoulb be 7 or 5 and some more
Thank you I had a test tomorrow
Thankyou!!
I'm trying to learn the LCM
Dude!!!!!! Come on man!!!
I wonder WHY you can multiply by the reciprocal to get the same result?
Currently in 4th grade and trying to learn this for 5th grade that way I won’t have to learn
Awosme
This comment is to the people who havent understood this video. So basically to divide fractions you have to first find the reciprocal(just invert it ex. 1/3=3/1) of the second number then you have to multiply it and thats it!
ex:
8/5 ÷ 2/3 =
8/5 x 3/2 =
~*24/10= 2 4/10*~
Epic😍
:( I didn’t get it . There was too much going on :(
So what I figured from this is just flip the other numbers around.
This video explains what is happening when you divide fractions and how to do it. If you want the shortcut, use the method “keep change flip”.
Keep the first fraction,
Change the division to multiplication,
Flip the second fraction.
Now it’s a multiplication problem. Easy. Multiply the top numbers. Multiply the bottom numbers for your new fraction.
Example. 2/3 divided by 4/5.
Keep the 2/3.
Change division to multiplication.
Flip 4/5 into 5/4.
Now it’s 2/3 x 5/4.
Multiply top numbers: 2 x 5 = 10
Multiply bottom numbers: 3 x 4 = 12
The answer is 10/12.
You can reduce the answer to 5/6 by dividing both parts of the fraction by 2.
@@darthader3507 you’re so helpful! i finally understand.
@@darthader3507 I'm sorry if this sounds dumb but do you always have to divide by 2?
@@darthader3507 ah nvm I see what your talking about. :)
Hello sir,i am recording similar lectures but i am not able to add this cursor. Can you please help me to add cursor like you in sketchbook.
Thanks
When the denominator is the same, you can just look at 8 divided by 1 = 8 and disregard looking at it as a fraction.
Can I join ur class
hard
Wow sir
There are some fraction sums that this doesn’t work for
8÷1=8, easy!
He says jumps and I just think of a frog doing math for some reason
Same tho
Kinda sounds like he's saying right turds
If only I understood what he was saying.
Didnt helpi need this dud to go to the main art
Heyoo! May i ask you how to solve this? 1/1/2 and 3/4/5 plss heeelp....
the 1st one is .5
I think his work is already late.......
mb bruh I was just tryn to help@@958rocket7
4 over three
Would this way work using the reciprocals of 1/3 and multiply it by 8/3
:D
lol sorry I like this guy but its = to its = to its = to 8
he repeats himself a lot and I think I could have made so spelling errors
Thank you so much I now know how to divide fractions.😁
🌈
Nice
I keep watching this and I just can't figure it out. I understand what 8/3rds is but when you get to multiplying it by 3 that's when I get lost. How can 8/3rds be the same as 24/3rds? . And when you say "Jumps" isn't more like if you had 8/3rds of pie divided by a 1/3rd ,well the 1/3rd will get all the 8 slices ?
+paul sha I was trying to figure it out too, I think he just didn't express his thoughts clear enough, and because he's comparing it to multiplication. 8/3rds divided by 1/3rd is apparently the same as 8/3rds times 3. The result is 24. 24 divided by 3 is 8. I'm still confused myself but I hope my thoughts help a bit. If you figured it out by now explain it to me better haha.
+Trevor M I think the confusing part is when he says "how many jumps to get to 8/3. I never learned fraction to great depth at school. The key to remember is the division sign ÷ means how many times does the 2nd number go into the first Example 4÷2 ,here 2 goes into 4 twice ,now use concept on his example 8/3 ÷ 1/3 here it says how many times does 1/3 go into 8/3. well you can see 8/3 is made up of 8 of those 1/3rds so the answer is 1/3 "goes in 8 times" not jumps! now there is a trick that's used to work it out faster just flip the second fraction and multiply the numerators and denominators.
paul sha I figured it out a little bit since my comment earlier. The part the that gets me is when it's questions like 9/5ths ÷ 7/3rds. I have a hard time thinking of the 7/3rds as fractions of the other fractions. I was never taught math in school so I've been learning it through Khan Academy
+Trevor M 9/5 ÷ 7/3 you can change this to equivalent fractions by multiplying the numerators and deminator by the same number and it won't change its value. So 9/5 becomes 27/15 (top and bottom multiplied by 3) and 7/3 becomes 35/15(×5 top and bottom) so it all becomes 27/15 ÷ 35/15. now they have common denominators it's easier to see and the question is " how many times does 35/15 fit in 27/15 " to me I'd say only one 27th of 35 can fit in. doing the flip of original equation 9/5 ÷ 7\3 = 9/5 × 3/7 =27/35 now I am thinking this is also saying only 27 of the 35 like found in the equivalent fractions above.
+Trevor M 9/5 ÷ 7/3 you can change this to equivalent fractions by multiplying the numerators and deminator by the same number and it won't change its value. So 9/5 becomes 27/15 (top and bottom multiplied by 3) and 7/3 becomes 35/15(×5 top and bottom) so it all becomes 27/15 ÷ 35/15. now they have common denominators it's easier to see and the question is " how many times does 35/15 fit in 27/15 " to me I'd say only one 27th of 35 can fit in. doing the flip of original equation 9/5 ÷ 7\3 = 9/5 × 3/7 =27/35 now I am thinking this is also saying only 27 of the 35 like found in the equivalent fractions above.
Most confused
So a/b ÷ 1/c = a/b * c?
And a/b ÷ c/d = a/b ÷ (d ÷ c)?
Makes sense to me