Answer:
The minimum number of books that should be tested is 312.
Step-by-step explanation:
The (1 - <em>α</em>)% confidence interval for population mean (<em>μ</em>) is:
The margin of error for this interval is:
The information provided is:
MOE = 0.10
<em>σ</em> = 0.90
Confidence level = 95%
Compute the critical value of <em>z</em> as follows:
*Use a <em>z</em>-table.
Compute the value of <em>n</em> as follows:
Thus, the minimum number of books that should be tested is 312.
