选择题
1999 AMC 8 Problem 10: Traffic Light Probability
A complete cycle of a traffic light takes 60 seconds. During each cycle the light is green for 25 seconds, yellow for 5 seconds, and red for 30 seconds. At a randomly chosen time, what is the probability that the light will NOT be green?
A.
1/4
B.
1/3
C.
5/12
D.
1/2
E.
7/12