6th grade (Illustrative Mathematics)
Learn to divide two fractions. The answer is a fraction. Created by Sal Khan.
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- is there another method to do this(8 votes)
- (Prepare for a long answer) Srivish, To answer your question, there IS another way to solve it. Cross multiplication. Here are some steps to help solve it
1: First take your Equation, and if you've already written an answer. Erase it, then write a new set of brackets to have your fractions in.
2: Secondly, take your equation. Let's ignore that division sign for now. So you have your two pairs of fractions, Correct?
3: TO do this, you will have to multiply a bit. First, take the numerator of your first fraction, and multiply it with the denominator of the second Fraction. This will turn into your new Numerator. Now cross off the fractions you just used.
4: Following this, Take your remaining fractions and multiply. This will turn into your new denominator. And complete your answer.
However, if your Equation with variables, such as X, the whole question will change. In order to adapt to this, you will have to change the way you solve it. Here is a link detailing how to.
Hope this helps!(18 votes)
- at 0.29 i didn't understand why we flipped it(8 votes)
- Because dividing is the same thing as multiplying by the reciprocal of a number. A reciprocal is basically just a number flipped upside down. Example: 4 ÷ 2 is the same thing as 4 * 1/2.(6 votes)
- How the heck does a reciprocal even work?! I'm mind blown. Can somebody tell me why?(6 votes)
- A reciprocal is the complete opposite of a fraction. you reverse the numerator and the denominator. It is used in division fraction. (i don't know why)(2 votes)
- Do you still have to do the extra math to the side to get the actual answer.(1 vote)
- how do you know when to cross multiply(3 votes)
- when it says 2 fractions with a multiplication sign next to it. eg: 2/3 X 5/3 is when to cross multiply. :)(2 votes)
- I don't get it how do you divid fractions(3 votes)
- you can just take the fraction on the right and switch the two numbers around (so the numerator becomes the denominator and the denominator becomes the numerator) then just multiply the two fractions and you have your answer!(1 vote)
- how do you multiply a fraction once its reached it max and has to become a whole fraction(2 votes)
- we can divide it as
as this is also reached its max but it can be divided and answer in decimal or fraction
there are many numbers which we have to divide and w get stuck in the same problem but it is not possible that a number in lowest term cannnot be divided we will get the answer but it will be in decimal and that is why decimals are made .
for eg 23/2=11.5
- I'm confused for when to simplify. I cut the numbers in half as much as I can. but when I get my answer it is wrong(2 votes)
- Sometimes you can't just keep cutting the numbers in half. If you get a decimal you should probably divide it by another number.
An example would be 18/33. If you split it in half, then the fraction would be 9/16.5, and that is not a correct fraction. You would have to divide it by 3, and that would get you 6/11, which is equal to 18/33. 6/11 is the lowest that you can simplify to, so that is your answer.
Hope this helps!
So let's calculate what 2/5 divided by 7/3 is, and I encourage you to pause this video and try to calculate this on your own. Well we just have to remind ourselves that this is going to be the exact same thing as 2 over 5 times the reciprocal of 7/3, which is 3 over 7. And then multiplying two fractions is pretty straightforward. This is just going to be equal to the product of the numerators. So 2 times 3 over the product of the denominators, over 5 times 7-- I'm trying to keep the colors consistent-- which of course is going to be equal to 2 times 3 is equal to 6. And 5 times 7-- I'll do this in a new color, let's see, I haven't used this shade of blue yet-- 5 times 7 of course is equal to 35. So this is equal to 6/35.