Question

In: Statistics and Probability

Exhibit F In order to estimate the average time that students spend on the internet per...

Exhibit F
In order to estimate the average time that students spend on the internet per day, data were collected for a sample of 36 business students. Assume the population standard deviation is 2 hours.

Refer to Exhibit F. If the sample mean is 6 hours, then the 95% confidence interval for the population mean,μ, is

Group of answer choices

4.35 to 7.65

5.67 to 6.33

5.35 to 6.65

6 to 6.65

Expert Solution

Solution :

Given that,

Point estimate = sample mean = =6

Population standard deviation = = 2

Sample size n =36

At 95% confidence level the z is ,

= 1 - 95% = 1 - 0.95 = 0.05

/ 2 = 0.05 / 2 = 0.025

Z/2 = Z0.025 = 1.96 ( Using z table )

Margin of error = E = Z/2 * ( / $\sqrt$ n)

= 1.96* (2 / $\sqrt$ 36 $\sqrt$ )

E= 0.65
At 95% confidence interval estimate of the population mean
is,

- E < < + E

6 - 0.65 <   <6 + 0.65

5.35<   < 6.65

( 5.35 to  6.65)

orchestra answered 2 years ago

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