Question

A traffc light located at 1st street and 5th Avenue has a red light for 75 seconds, a green light for 120 seconds, and a yellow light for 5 seconds, if you are traveling on 5th Avenue. If a person arrives at the light at a random time, find the probability of the light being NOT being red when the person arrives?

Answer 1

Explanation:

The total time is 75 + 120 + 5 = 200 seconds.

The light is red for 75 seconds, and not red for 125 seconds.

The probability that the light will not be red is 125 / 200 = 0.625, or 62.5%.

Or, we could solve it this way:

The probability of the light being red is 75 / 200 = 0.375, or 37.5%.

So the probability of not being red is 1 − 0.375 = 0.625, or 62.5%.