Answer:
If you need to convert from a LARGER unit to a SMALLER unit, MULTIPLY. If you need to convert from a SMALLER unit to a LARGER unit, DIVIDE.
Explanation:
The basic rule is: If you need to convert from a LARGER unit to a SMALLER unit, MULTIPLY. If you need to convert from a SMALLER unit to a LARGER unit, DIVIDE. You will make the number smaller and, as you already know, division is all about making numbers smaller.