A Single Population Mean Using the Student's t-Distribution · Exercise 31

A major business magazine published data on the best small firms in 2012. These were firms that have been publicly traded for at least a year, have a stock price of at least $5 per share, and have reported annual revenue between $5 million and $1 billion. shows the ages of the corporate CEOs for a random sample of these firms.

$$\begin{array}{ccccc}\text{48}& \text{58}& \text{51}& \text{61}& \text{56}\\ \text{59}& \text{74}& \text{63}& \text{53}& \text{50}\\ \text{59}& \text{60}& \text{60}& \text{57}& \text{46}\\ \text{55}& \text{63}& \text{57}& \text{47}& \text{55}\\ \text{57}& \text{43}& \text{61}& \text{62}& \text{49}\\ \text{67}& \text{67}& \text{55}& \text{55}& \text{49}\end{array}$$
Use the sample data to construct a 90 percent confidence interval for the mean age of CEOs for these top small firms. Use the Student's t-distribution.

Its source prints no answer for this problem, so there's nothing to check against.

OpenStax, Statistics · §8.2 A Single Population Mean Using the Student's t-Distribution · Exercise 31