Although it may look intimidating, it's just lots of little problems. I'll do a few for you and let you do the rest so you actually get a learning experience the way this site was designed.
Basically all you do is multiply the numerator by the number you need to multiply by.
3/8
10/3
16/9
8/7.
If you need to simplify, you should be able to do that on your own.
