1. The mean age of College students is 25. A certain class of 33students has a mean age of 22.64 years. Assuming a populationstandard deviation of 2.87 years, at the 5% significance level, dothe data provide sufficient evidence to conclude that the mean ageof students in this class is less than the College mean?
a. Set up the hypotheses for the one-mean ?-test. ?0:Â Â Â ??:
b. Compute the test statistic. Round to two decimal places.
c. Sketch a normal curve, mark your value from part (b), andshade in the area(s) we are interested in. Determine the?-value.
d. Determine if the null hypothesis should be rejected.
e. Interpret your result in the context of the problem in asentence.
A study examined the effects of an intervention program toimprove the conditions of urban bus drivers. Among other variables,the researchers monitored diastolic blood pressure of bus driversin a large city. The data, in millimeters of mercury (mm Hg), arebased on the blood pressures obtained prior to intervention for the41 bus drivers in the study. At the 10% significance level, do thedata provide sufficient evidence to conclude that the meandiastolic blood pressure of bus drivers in the city exceeds thenormal diastolic blood pressure of 80 mm Hg? The mean of the datais ? = 81.95122 mm Hg, and the standard deviation of the data is ?= 10.537911 mm Hg.
a. Set up the hypotheses for the one-mean ?-test. ?0:Â Â ??: Â Â
b. Compute the test statistic. Round to two decimal places.
c. Sketch a ?-curve, mark your value from (b), and shade in thearea(s) we are interested in. Determine the ?- value.
d. Determine if the null hypothesis should be rejected.
e. Interpret your result in the context of the problem in asentence.
