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Sleepless nights How much sleep do high school students get on a typical

school night? A counselor designed a survey to find out. To make data collection easier,

the counselor surveyed the first 100students to arrive at school on a particular morning.

These students reported an average of 7.2 hours of sleep on the previous night.

a. What type of sample did the counselor obtain?

b. Explain why this sampling method is biased. Is7.2hours probably greater than or less

than the true average amount of sleep last night for all students at the school? Why?

Short Answer

Expert verified

a) The subjects can decide whether or not they want to be included in the sample.A convenience sample is frequently text biased, because the fipersons will have slept less because they arrived earlier.

b) They have data about the strongest opinions, resulting.We estimate the average of 7.2hours to be less than the actual average.

Step by step solution

01

Part (a) Step 1: Given information

We have to tell about type of sample did the counsellor obtain.

02

Part (a) Step 2: Explanation

Because the student conveniently surveyed the first 100students, the sample in the activity prompt is a text convenience sample convenience sample. A convenience sample is frequently text biased, because the first100persons will have slept less because they arrived earlier, whereas students who arrived later will have slept longer.

03

Part (b) Step 1: Given information 

We have to tell about true average amount of sleep last night.

04

Part (b) Step 2: Explanation

A convenience sample is frequently textbfbiased, because the first 100persons will have slept less because they arrived earlier, whereas students who arrived later will have slept longer. We estimate the average of 7.2hours to be less than the actual average because the first 100students are likely to have slept less than the other pupils.

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