Converting between units can be challenging because it doesn't really make sense. When you convert feet into yards, like Elisha said, you will DIVIDE BY 3. However, when you convert feet into inches, you will MULTIPLY BY 12. The part that confuses people is when to multiply and when to divide.
Imagine you are walking across a 27 ft. room, taking steps that are 1 yd long. You will get to the other side quickly, taking only 9 steps. (Divide when you convert to larger units to get fewer of them.)
Now imagine you are walking across the same room, but your steps are only 1 in. long. That will take forever! It will actually take you 324 steps. (Multiply when you convert to a smaller unit to get more of them.)
Hope that helps! You will always either multiply or divide with any type of unit conversions.