Question

In: Statistics and Probability

A typical college student spends an average of 2.55 hours a day using a computer. A...

A typical college student spends an average of 2.55 hours a day using a computer. A sample of 13 students at The University of Findlay revealed the sample mean of 2.70 hours and sample standard deviation of 0.51 hours.

Can we conclude that the mean number of hours per day using the computer by students at The University of Findlay is the same as the typical student’s usage? Use the five step hypothesis testing procedure and the 0.05 significance level.

Expert Solution

a)

H0: = 2.55

Ha: 2.55

b)

Test statistics

t = ( - ) / ( S / sqrt(n) )

= ( 2.70 - 2.55) / ( 0.51 / sqrt(13) )

= 1.06

c)

Critical values at 0.05 significance level with 12 df = -2.179 , 2.179

d)

Rejection rule = Reject H0 , it t < -2.179 OR t > 2.179

Decision = Since test statistics falls in non-rejection region, fail to reject H0.

e)

Conclusion = We do not have sufficient evidence to support the claim.

orchestra answered 2 years ago

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