Question

A simple random sample of 31 men from a normally distributed population results in a standard deviation of 10.8 beats per minute. The normal range of pulse rates of adults is typically given as 60 to 100 beats per minute. If the range rule of thumb is applied to that normal​ range, the result is a standard deviation of 10 beats per minute. Use the sample results with a 0.05 significance level to test the claim that pulse rates of men have a standard deviation equal to 10 beats per minute. Complete parts​ (a) through​ (d) below.

Answer 1

Null hypothesis H0: = 10 beats per minute

Alternative hypothesis Ha: 10 beats per minute

Given the significance level , = 0.05

Test statistic,

Degree of freedom = n - 1 = 31 - 1 = 30

p-value = P(> 34.992, df = 30) = 0.2429

Since p-value is greater than , we fail to reject null hypothesis H0 and conclude that there is no strong evidence that standard deviation is not equal to 10 beats per minute.