You should have given an examples: so, if I want to convert 4 2/3 into a fraction, this is what you do:
Multiply the bottom number(3) X 4=12, then ADD the (2) on the top to the number we just got like this: 12 + 2=14. This is the top number of your fraction, and the bottom number(3) doesn't change. So, we put one on top of the other like this: 14/3. And that's all. Hope you understand it now. Good luck.