8.78 Grandpas using e-mail When the GSS asked in 2012,

“About how many hours per week do you spend sending and answering e-mail?” the nine males in the sample of age at least 80 responded:

0, 0, 0, 1, 2, 3, 4, 4, 13

a. The TI@83+>84 screen shot shows results of a statistical analysis for finding a 90% confidence interval.

Explain what each line represents.

b. Verify the computation of the interval and interpret it.

c. Explain why the population distribution may be skewed right. If this is the case, is the interval you obtained in part b useless, or is it still valid? Explain.

Transcribed Image Text:

NORMAL FIX3 AUTO REAL RADIAN CL TInterval (.463.5.537) x=3.000 Sx=4.093 n=9.000 0