Jim is helping his dad cook hamburgers for his family and friends. There are 15 people. Each person wants two hamburgers. Three people want hamburgers with cheese. Two people want hamburgers with mustard. Two people want hamburgers with catsup. The rest want them plain. How many plain hamburgers will Jim and his dad make?
A: 8
B:16
C:21
D:23
The number of people who do not want plain hamburgers is 3+2+2 = 7, so 15-7 = 8 people want plain hamburgers. Each person wants 2 hamburgers, for a total of ...
