Multiplying Rational Numbers

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I am stuck. I can multiply fractions, ie 11/14 x 7/33, but when it comes to a problem like 2 9/10 x 1 1/5 or one like 4x/3y x 9y/2x I don't understand how to do it. Can someone please help?
 
To multiply (or divide) mixed numbers, convert them first to improper fractions. Then multiply (or divide) as usual. If necessary, convert the result back into mixed-number form.

Hope that helps.

Eliz.
 
In regards to improper fractions, you need to make them proper before you multiply them together:

Your example: 2 9/10 • 1 1/5

To change this into an improper fraction, multiply the denominator by the number sitting outside of the fraction, and then add the numerator. So the first fraction (2 9/10) would become 29/10. The second one would be (5•1)+1, which is 6/5.

Then multiply like you normally do.

With your variable problems, multiply across like you normally would and combine like terms.

Your problem is 4x/3y•9y/2x. Multiplying across, you would get 36xy/6xy. You can take 6xy out, because both the numerator and the denominator share these terms. You would then end up with a plain old 6 as your answer.

Now, try these:

5 3/4 • 10 2/8

3x/3y • 9y/5x
 
Thank you very much. Yall are life savers.
One more question

I understand that the letters cancel each other out. So, if I have a problem like this (i don't know how to do the little 2 for the squared, so i will type it out)

x squared/4y x 16y squared/3x wouldn't I simplify it, and get 4xy/3 ?
 
(x^2)/4y . (16 y^2)/3x

= (x^2) (16 y^2) / (4y . 3x)

= ( 16/(4.3) ) (x^2/ x) (y^2/y)

= (4/3) (x) (y)

=(4/3) xy

did it this way just to show you the layout.
So yes you are correct.
 
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