A study claim that students in two-year college work on average of 20 hours a week....

A study claim that students in two-year college work on average of 20 hours a week. A teacher wanted to test this claim. She took a sample of 12 students and asked them about the number of hours they work per week. The following are their responses:

14 25 22 8 16 26 19 23 41 33 21 20

Assume that the number of hours worked by all two-year college students is normally distributed.

a.Calculate the (approximate) value of the 85th percentile

b. Find the percentile rank of 20.

c. Find the sample mean and sample standard deviation of these 12 students.

d. Using a 0.05 significance level, can you conclude that the claim of the study is true?

Solutions

Expert Solution

Hence we can conclude that the claim of teacher is true that college work is 20 hours in week.

orchestra answered 1 year ago

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