A survey asked students if they preferred to sit in the fron

A survey asked students if they preferred to sit in the front, middle, or back of the class and also asked them their heights. The following data are the heights for 15 female students who said they prefer to sit in the back of the class.

68, 62, 65, 69, 68, 69, 64, 66, 69, 68, 62, 64, 67, 68, 65

The mean height for the population of college females is 65 inches. Test the claim that the mean height for females who prefer to sit in the back of the room is higher than it is for the general population. In other words, test whether females who prefer to sit in the back of the room are taller than average. Use alpha = 0.05.

Solution

68, 62, 65, 69, 68, 69, 64, 66, 69, 68, 62, 64, 67, 68, 65

mean : 66.27

SD : 2.46

Ho : miu = 65

H1 : miu > 65

for alpha =0.05

df = 14

critical value : 1.761

reject Ho if T>1.761

T = 66.27 - 65 / [2.46 / srqt(15)]

T = 1.999

we reject Ho

conclusion

there is evidence to accept the claim that the mean height for females who prefer to sit in the back of the room is higher than it is for the general population