+495 To do this, you need to have common denominators. The quickest way to get common denominators is multiply your entire fractions by the denominator over the denominator of the other fraction. Sorry if that sounds confusing, it looks like this:
5/8 * (7/7) - 4/7 * (8/8)
which simplifies to
35/56 - 32/56
and from here you can subtract the numerators normally.
= 3/56
