Question

the accompanying data contains the monthly retail sales ($millions) of a large country’s women’s clothing stores for 70 months. A sample taken from this population to estimate rhe average sales in this time period is shown below. Complete parts a through d below.

3,053 2,392 2,947 2,850 3,076 2,390 3125

2,345 2,639 3,112 2,329 3,061 2,855 3,128

3,039 2,721 2,884 2,612 2,527 3,069 2,387

2,964 2,516 2,831 2,856

a. calculate the population mean.

b. calculate the sample mean.

c. how much sampling error is present in this sample?

d. determine the range of possible error if 25 sales figures are sampled at random from this population.(round to two decimal places as needed. Use ascending order.)

Answer 1

a)
population mean = 2788

b)
sample mean = 2788

c)sample sd = 278.8969
sampling error = 278.8969/sqrt(25) = 55.7794

d)
Range of possible error
(2788 - 55.7794, 2788 + 55.7794)
(2732.22, 2843.78)