Probability Question 43
Question: 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, the probability that the light will not be green is
Options:
A) $ \frac{1}{3} $
B) $ \frac{1}{4} $
C) $ \frac{4}{3} $
D) $ \frac{7}{12} $
Answer:
Correct Answer: D
Solution:
- [d] Total time of a cycle $ =60\sec $ Time of green light $ =25\sec $
$ \therefore $ Probability that light is green $ =\frac{25}{60} $
$ \therefore $ Probability that light will not be green $ 1-\frac{25}{60}=\frac{7}{12} $