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Traffic Light Green Probability

1050BeginnerCombinatoricsProbability

AMC 8 · 1999 · Problem 10

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?

Answer choices

A
\frac{1}{4}
B
\frac{1}{3}
C
\frac{5}{12}
D
\frac{1}{2}
E
\frac{7}{12}
0 students attempted0% solvedRating 1050

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