1) A simple random sample of 50

men from a normally distributed population results in a standard deviation of 11.1 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 0.10

significance level to test the claim that pulse rates of men have a standard deviation equal to 10

beats per minute.

find the P value.

2) The piston diameter of a certain hand pump is 0.6 inch. The manager determines that the diameters are normally distributed, with a mean of

0.6 inch and a standard deviation of 0.004 inch. After recalibrating the production machine, the manager randomly selects 23 pistons and determines that the standard deviation is 0.0036

inch. Is there significant evidence for the manager to conclude that the standard deviation has decreased at the =0.01 level of significance?

calculate the value of the test statistic and find the p value.

3) Suppose a mutual fund qualifies as having moderate risk if the standard deviation of its monthly rate of return is less than 5%. A mutual-fund rating agency randomly selects 26 months and determines the rate of return for a certain fund. The standard deviation of the rate of return is computed to be 3.64%. Is there sufficient evidence to conclude that the fund has moderate risk at the

=0.01 level of significance? A normal probability plot indicates that the monthly rates of return are normally distributed.

calculate the value of the test statistic and find the p value

4) Workers at a certain soda drink factory collected data on the volumes (in ounces) of a simple random sample of 21 cans of the soda drink. Those volumes have a mean of 12.19 oz and a standard deviation of

0.11 oz, and they appear to be from a normally distributed population. If the workers want the filling process to work so that almost all cans have volumes between 11.93oz and 12.57oz, the range rule of thumb can be used to estimate that the standard deviation should be less than0.16oz. Use the sample data to test the claim that the population of volumes has a standard deviation less than

0.16oz. Use a 0.01 significance level.

find the p value.

5)A simple random sample of 28 filtered 100-mm cigarettes is obtained from a normally distributed population, and the tar content of each cigarette is measured. The sample has a standard deviation of 0.22 mg. Use a 0.05 significance level to test the claim that the tar content of filtered 100-mm cigarettes has a standard deviation different from

0.35 mg, which is the standard deviation for unfiltered king-size cigarettes.

find the p value of the test statistic