# hard fraction

• December 10th 2010, 07:55 AM
andyboy179
hard fraction
hi,
how would i work this out, Attachment 20052
would i do:
Attachment 20053
= Attachment 20054

but what do i do after this?
• December 10th 2010, 08:57 AM
BariMutation
To subtract ANY two fractions, you don't need a common denominator. Yes, it helps, but it's not needed. What I would do is this;

Multiply the numerator of the first one and the denominator of the second one. Now multiply the denominator of the first one and the numerator of the second one. Subtract these two values, and this will be the numerator of the answer. For the denominator of the answer, simply multiply the two denominators together. So, in essence;

$a/b - c/d = (ad - bc)/(bd)$

It looks complicated, but take this example;

$5/6 - 7/9 = (45 - 42)/54$
• December 10th 2010, 09:03 AM
andyboy179
ok i know what to do now, thanks!!!