To compare fractions, you must first change them so they have the **same** denominator.

Compare ^{2}/_{3} and ^{3}/_{5} and find out which fraction is bigger.

First look at the denominators (the bottom numbers).

Find a new number that both denominators go into:

Try 9 - you can divide 9 by 3 but you can't divide 9 by 5.

Try 10 - you can divide 10 by 5 but not by 3, so that isn't right either.

Try 15 - you can divide 15 by 5 (which equals 3) and you can also divide 15 by 3 (which equals 5), so 15 is the new denominator.

Now you have found a new denominator that is divisable by both numbers, you need to change the numerators (the top numbers).

To change the numerators, simply multiply them by the number of times the denominator goes into 15.

So for

^{2}/_{3}- 3 goes into 15 five times, so you must multiply the numerator (2) by 5 which equals 10.And for

^{3}/_{5}- 5 goes into 15 three times, so you must multiply the numerator (3) by 3 which equals 9.

So now both fractions have been changed you can compare them to see which fraction is the biggest. ^{10}/_{15} is **bigger** than ^{9}/_{15} so the biggest original fraction is ^{2}/_{3}.

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