Introductory Statistics | Edition, Chapter 7, Problem 61P -

Previously, De Anza statistics students estimated that the amount of change daytime statistics students carry is exponentially distributed with a mean of $0.88. Suppose that we randomly pick 25 daytime statistics students.

f. Find the probability that the average of the 25 students was between $0.80 and $1.00.

The answer already posted is not helping me to learn to resolve this problem.

Thank you!