THE CORRECT ANSWER IS (E). REFERRING TO THE ICE CREAM FLAVORS AS A,...

9. The correct answer is (E). Referring to the ice cream flavors as A, B, C, and D, there

are 10 possible two-scoop combinations:

A

1

either A, B, C, or D

B

1

either B, C, or D

C

1

either C or D

D

1

D

For each of these 10 combinations, either of two toppings can be used. Thus, the total

number of different types of sundaes is 20.