Q25:
The buyer of a new home must choose 2 of 4 types of flooring and 2 of 6 paint colors. How many different combinations of type of flooring and paint color are available to the home buyer?
A. 4
B. 24
C. 48
D. 90
E. 96Answer: D
就只要C(2,4)*C(2,6)就可以了么？ 我怎么觉得还要乘4，因为这四种选出来后两两得再搭配 | 
