Question

A clinic offers a​ weight-loss program. The table below gives the amounts of weight​ loss, in​ pounds, for a random sample of 20 of its clients at the conclusion of the program. Assume that the data are normally distributed. Complete parts​ (a) and​(b).

10	11	12	24	20	21	7	8	18	19
17	5	15	8	17	16	13	16	14	23

a.Find a 98​% confidence interval for the population mean.

The 98% confidence interval is from a lower limit of ___  to an upper limit of ___. (Round to two decimal places as​ needed.)

b.Without doing the​ calculations, explain whether a 90% confidence interval for the population mean would be wider​ than, narrower​ than, or the same as that found in part​ (a). Choose the correct answer below.

A.It will be narrower because the margin of error will be smaller for a 90% confidence interval than for a 98% confidence interval.

B.It will be the same because the confidence interval is being calculated for the same data set.

C.It will be wider because the margin of error will be smaller for a 90% confidence interval than for a 98% confidence interval.

D.It will be wider because the margin of error will be larger for a 90% confidence interval than for a 98% confidence interval.

Answer 1