Solution :
Given that,
Population standard deviation = = 30
Margin of error = E = 15
Z/2 = 2.576
sample size = n = [Z/2* / E] 2
n = [2.576 * 30 / 15]2
n = 27
Sample size = n = 27
Multiple Choice Question An engineer wishes to determine the average time (in seconds) required to drill...
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