What if we need to add

3 + 7/8 ?

Hey, remember, that's just 3 7/8.

Done!

That was easy, but, what about mixed numbers?

How about this?

3 2/5 + 1 4/7

All we have to do is change these to improper fractions... Then we can add them!

Get it?

Do you see that 3 2/5 - 1 4/7 will work the same way?