4. Alice had 3/4 lb. of candy. She gave 1/3 lb. of the candy to Scott. How much candy does she have left?

A nice simple subtraction problem, because the wholes stay the same:

Alice had 3/4 lb. of candy. She gave 1/3 lb. of the candy to Scott. How much candy does she have left?

3/4 - 1/3 lb is left