Question

First question like this any info, steps, or particulars appreciated.

One hundred eight Americans were surveyed to determine the number of hours they spend watching television each month. It was revealed that they watched an average of 151 hours each month with a standard deviation of 32 hours. Assume that the underlying population distribution is normal. Construct a 99% confidence interval for the population mean hours spent watching television per month.

(a) State the confidence interval,

(b) sketch the graph

(c) calculate the error bound.

this is a data analysis for decision making question

Answer 1

a) At 99% confidence interval the critical value is z^* = 2.58

The 99% confidence interval for the population mean is

+/- z^* * s/

= 151 +/- 2.58 * 32/

= 151 +/- 7.944

= 143.056, 158.944

b)

c) Margin of error = z^* * s/

                         = 2.58 * 32/

                         = 7.944