SOLUTION: Thank you very much Fombitz. Now i have another quick question. Why can i multiply by 5/2 and not 2/5. Please I need a refresher. Thanks a lot you guys are great

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: Thank you very much Fombitz. Now i have another quick question. Why can i multiply by 5/2 and not 2/5. Please I need a refresher. Thanks a lot you guys are great      Log On


   

Question 176354: Thank you very much Fombitz.
Now i have another quick question. Why can i multiply by 5/2 and not 2/5. Please I need a refresher.
Thanks a lot you guys are great
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
To go from
%282x%29%2F%285y%29
%282%2F5%29%28x%2Fy%29
to
%28x%2Fy%29
you need to use the multiplicative inverse of the coefficient in front of %28x%2Fy%29.
The multiplicative inverse of (2/5) is (5/2) since
%282%2F5%29%285%2F2%29=1
So then you multiply both sides by (5/2), to get %28x%2Fy%29 by itself on the left hand side.
.
.
.
If you multiply both sides by (2/5), you'd get,
%282%2F5%29%28x%2Fy%29=3%2F4
%282%2F5%29%282%2F5%29%28x%2Fy%29=%282%2F5%29%283%2F4%29
%284%2F25%29%28x%2Fy%29=3%2F10