A random sample of 22 students' weights is drawn from the student population.
Investigate whether the average weight of the student population is different from 140 lb.
135 119 106 135 180 108 128 160 143 175 170
205 195 185 182 150 175 190 180 195 220 235
State the null and alternative hypothesis (Ho and Ha).
What are the n, X, s?
Compute the t-statistic. What is the degree of freedom (df)?
Find the P-value from the table-D.
Test the hypothesis at the significance level α=0.05. Reject Ho or Ha? Why?
What conclusion can you make about the mean weight of students?
Construct a 95% Confidence Interval for the students' mean weight.
What value for t* should you use? Find the t* value from table-D.
Do the calculation for the 95% Confidence Interval.
Based on the 95% Confidence Interval, what conclusion can you make about the hypothesis in a)? Why?