Question

In: Statistics and Probability

The length of time junior high school students sleep per night follows an approximate uniform distribution...

The length of time junior high school students sleep per night follows an approximate uniform distribution from seven to eleven hours. Suppose we randomly select a junior high student.

1. Find the probability that the randomly selected student sleeps less than 8 1/2 hours per night.

A. 0. 375

B. 0. 4705

C. 0. 7727

D. . 2143

2. On average, how long does a junior high school student sleep per night ?

A. 9 hours

B. 8 hours

C. 4 hours

D. 11 hours

3. Find the probability that the randomly selected student sleeps eight to twelve hours per night?

A. 0. 4705

B. 0. 375

C. 0. 7727

D. . 2143

4. 65 % of junior high school students sleep at least how many hours ?

A. 8. 4 hours

B. 7. 8 hours

C. 6. 5 hours

D. 9. 6 hours

Solutions

Expert Solution

orchestra answered 1 year ago
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