For the Metric System, let's review our mnemonic device:
Customary units mainly deals with the length measurement. Length measurement is important for lots of different reasons. Measurement of length have lots of applications in real life, like it helps you to know how far you have traveled, how far you have left to travel, how tall you are, distance and many other things. The system for measuring length in the United States is called customary system based on the inch, foot, yard, and mile, which are the only four customary length measurements in their everyday use.
Although there isn't an easy way to remember the conversions for the Customary System, we do have a way to help us remember whether to multiply or divide to get the correct answer.
Horse to fly, we multiply.
Fly to horse, divide of course.
For more practice with measurement convertions, go to this website.