Answer:
0.3108 is the probability that the sample mean is between 7.8 and 8.2 minutes.
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 8 minutes
Standard Deviation, σ = 2.5 minutes
Sample size, n = 25
We are given that the distribution of time spent is a bell shaped distribution that is a normal distribution.
Formula:
Standard error due to sampling =
P(sample mean is between 7.8 and 8.2 minutes)
0.3108 is the probability that the sample mean is between 7.8 and 8.2 minutes.