In a psychological testing experiment, 100 subjects are selected randomly and their reaction time, in seconds, to a particular stimulus is measured.
Past experience suggests that the population standard deviation in reaction times to these types of stimuli is 4 seconds and that the distribution of reaction times is approximately normal.
The (sample) average time for the subjects is 16 seconds.
Give an upper 97.5% bound (one-sided) for the mean reaction time.
Write your answer with 3 digits after the decimal point. For example, 0.782 or 0.352.