Question

Listed below are the ages (years) of randomly selected race car drivers. Construct an 80% confidence interval estimate of the mean age of all race car drivers. 32 32 33 33 41 29 38 32 33 23 27 45 52 29 25.

Answer 1

32	-1.6	2.56
32	-1.6	2.56
33	-0.6	0.36
33	-0.6	0.36
41	7.4	54.76
29	-4.6	21.16
38	4.4	19.36
32	-1.6	2.56
33	-0.6	0.36
23	-10.6	112.36
27	-6.6	43.56
45	11.4	129.96
52	18.4	338.56
29	-4.6	21.16
25	-8.6	73.96

Refer t-table or use excel function "=T.INV.2T(0.20,14)" to find the critical value of t.

One can be 80% confident that the population mean age of all race car drivers is from