Assignment:
Q1. A machine produces 5-inch nails. A sample of 12 nails was selected and their lengths determined. The results are as follows:
4.94 4.94 5.07 4.91 4.98 5.00 4.94 5.09 5.00 4.92 5.08 5.06
Assuming that a = 0.10, test the hypothesis that the population mean is equal to 5.
State the null and alternate hypotheses
Calculate the mean and standard deviation
Determine which test statistic applies, and calculate it
Determine the critical value(s).
State your decision: Should the null hypothesis be rejected?
Q2. The pulse rates below were recorded over a 30-second time period, both before and after a physical fitness regimen. The datais shown below for 8 randomly selected participants. Is there sufficient evidence to conclude that a significant amount of improvement took place? Assume pulse rates are normally distributed. Test using a = 0.05.
State the null and alternate hypotheses
Calculate the mean and standard deviation
Determine which test statistic applies, and calculate it
Determine the critical value(s).
State your decision: Should the null hypothesis be rejected?
Before 43 34 37 41 41 59 36 58
After 37 36 40 49 52 51 31 55
Q3. You are given the following data. Test the claim that there is a difference in the means of the two groups. Use a = 0.05.
Group A Group B
xbar1 = 10 xbar2 = 4
s1 = 15 s2 = 19
n1 = 89 n2 = 69
State the null and alternate hypotheses
Determine which test statistic applies, and calculate it
Determine the critical value(s).
State your decision: Should the null hypothesis be rejected?