Question

In: Statistics and Probability

Suppose that during an unexpected snowstorm, Mr. Wong decided to take a random sample of students...

Suppose that during an unexpected snowstorm, Mr. Wong decided to take a random sample of students in his AP Statistics class to examine their arrival times, in minutes. He compared the difference between the students' arrival time with the time the class was supposed to begin.

Mr. Wong asks you, his assistant, to use the information below to answer the following questions (negative value means that the student arrived BEFORE class began).

Number of students

30

Mean

-1.067

Q1

-24

Q3

18

Q2

-10.5

Min

-41

Max

53

Variance

765.78850575713

Standard deviation

27.67288394344

* Please do not copy other experts' solutions, thank you!

Question A: Mr. Wong would like to determine if his students arrive to class late on average. He asks you to perform a hypothesis test @ 10% significance level. Clearly state the conclusion you would tell Mr. Wong using a critical value.

Question B:

i) Mr. Wong asks you to calculate a 90% confidence interval for the average difference in time.

ii) Interpret the interval you calculated.

iii) Based on the interval, what can you say about Mr. Wong's AP Statistics class's arrival time?

Question C: Did you expect the conclusion in Question B to be the same as the conclusion in Question A? Explain why or why not.

Solutions

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