Chapter 13, Problem 14CT

To determine

The probability that randomly selected students at the college is between $18$ and $20$ years old, if the age distribution of the student at a community college is as follows;

$\begin{array}{ccccccc}\text{Age}& \text{17}\text{and}\text{under}& 18-20& 21-24& 25-34& 35-64& \text{65}\text{and}\text{over}\\ \text{Probability}& 0.03& ???& 0.23& 0.29& 0.25& 0.01\end{array}$.