Wednesday

July 23, 2014

July 23, 2014

Posted by **kay** on Wednesday, March 13, 2013 at 4:23pm.

- math -
**Steve**, Wednesday, March 13, 2013 at 4:29pmYou can't cross-multiply two fractions. It doesn't mean anything. You cross-multiply when you have an equation with fractions, as in

2/3 = 8/12

Then you multiply the left by thr right-side denominator, and vice-versa:

2*12 = 3*8

24 = 24

It's a handy way of getting rid of fractions. What you are really doing is putting everything all over a common denominator, without keeping it around.

2/3 = 8/12

LCD = 36, so

2*12/3*12 = 8*3/12*3

24/36 = 24/36

and you just toss the 36 away, since it no longer affects anything. If two fractions with the same denominator have equal numerators, then they are equal.

If you just want to multiply fractions, your question about

1/2 * 4/22 = (1*4)/(2*22) = 4/44 = 1/11

or, since 1/2 of 4 is 2,

1/2 * 4/22 = 2/22 = 1/11

**Related Questions**

Math - could you tell me three equivalent fractions for each: 2/3 8/16 4/10 3/4 ...

Math - How do you divide fractions??? Cross multiply: For example, 4/5 divided ...

Math--need help fast - If the radius of a circle is x/6, what's the diameter and...

Distributive property - How would I multiply these expression? 6(h-4) -3(x+8) -...

intro cal - the first 3 term of a geometric progression are k-4, 2k-4, 4k+4. ...

Math - I need to express the following in equivalent form: m-2/m^2-5m+6 , 2x+6/x...

5th Grade Math - I cannot get my brain around questions like this: 1/4 divided ...

math - Prove this identity (cos è - 1) / (cos^2 è) = sec è - sec^2 è I have a ...

pre-algebra - how do i solve proportions??? please help!! And how do i kno what ...

Algebra-I really need help, please? - I have to solve sqrt(2x-7) >=5 answers ...