Question

The weekly time (in hours) spent on homework by 20 college student has a sample mean...

The weekly time (in hours) spent on homework by 20 college student has a sample mean of 12.2 hours and a sample standard deviation of 1.8 hours. Construct a 99% confidence interval.

Math   Statistics-And-Probability   
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Answer #1

Solution :

Given that,

t /2,df = 2.861

Margin of error = E = t/2,df * (s /n)

= 2.861 * (1.8 / 20)

Margin of error = E = 1.2

The 99% confidence interval estimate of the population mean is,

- E < < + E

12.2 - 1.2 < < 12.2 + 1.2

11 < < 13.4

(11, 13.4)

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