Chapter 6.3, Problem 14MC

Jim is not sure when to use multiplication by a fraction and when to use division. He has the following list of problems. How would you help him solve these problems in a way that would enable him to solve similar problems on his own?

a. $\frac{3}{4}$ of a package of sugar fills $\frac{1}{2}\text{c}$. How many cups of sugar are in a full package of sugar?

b. How many packages of sugar are needed to fill $2\text{c}$?

c. If $\frac{1}{3}\text{c}$ sugar is required to make two loaves of challah, how many cups of sugar are needed for three loaves?

d. If $\frac{3}{4}\text{c}$ sugar is required for $1\text{gal}$ of punch, how many gallons can be made with $2\text{c}$ of sugar?

e. If you have $22\frac{3}{8}\text{in}.$ of ribbon, and need $1\frac{1}{4}\text{in}.$ to decorate one doll, how many dolls can be decorated, and how much ribbon will be left over?