Question

Question 7 (1 point)
A survey asks this question "How long did you spend on shopping in the past week?" The responses (in hours) of 15 people are given below:

3, 0, 4, 1, 6, 1, 2, 4, 5, 2, 5, 4, 2, 5, 3

Find a 95% confidence interval for the mean number of hours people spent on shopping in the past week.

Question 7 options:

2.18 to 4.14

2.15 to 4.11

2.07 to 4.03

1.94 to 3.90

Answer 1

From the given data

n = 15 , xbar = 3.13 , s = 1.77

The 95% confidence interval for population mean is

xbar - E < < xbar + E

Where E = t​​​​​​a/2*( s/√n)

For a = 0.05 and d.f = n -1 = 14

t​​​​​​a/2 , n-1 = t​​​​​​0.025, 14 = 2.14

E = 2.14 *(1.77/√15)

E = 0.98

3.13 - 0.98 < < 3.13 + 0.98

2.15 < < 4.11

So 95% confidence interval for population mean is from 2.15 to 4.11