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%.