Question

a survey was conducted to estimate the average number of hours that people spent exercising per week. a random sample of 450 people was taken, and the sample and the mean was found to be 6 hours with a standard deviation of 2.5 hours. calculate the 95%, 90%, and 80% of confidence intervals on a single number line

Answer 1

Confidence interval: (1760,1956)

Explanation:

We are given the following information in the question:

Sample size, n = 81

Sample mean =

Population standard deviation =

Confidence Level = 95%

Significance level = 5% = 0.05

Confidence interval:

Putting the values, we get,

Answer 2

95% Confidence Interval: 4.8 to 7.2

90% Confidence Interval: 5.0 to 7.0

80% Confidence Interval: 5.4 to 6.6