EDIT-if you subtracted 25-14=11, 7/8 is a little larger than 5/6,so when you subtract the whole #, it should be under 11.

The easiest way to go about doing this would be to make both fractions top-heavy.

So for the first one, work out what 25 is in terms of 1/6ths (multiply it by 6) and add the additional 5/6. This gives you a fraction 155/6. The second one, calculated the same way, gives 117/8.

To do a subtraction, we need to have the same denominator.

The lowest common multiple of 8 and 6 is 24, so we need to give each fraction expressed in 1/24ths

6 * 4 = 24 so 155 * 4 / 6 * 4 = 155/6

620/24

8 * 3 = 24 so 117 * 3 / 8 * 3 = 117/8

351/24

So the sum is now 620/24 – 351/24

This is equivalent to (620 – 351)/24 = 269/24

Returning it to a mixed fraction

11 5/24m is left