1. Elena would like to know the average height of seventh graders in her school district. She measures

the heights of everyone in a random sample of 20 students. The mean height of Elena's sample is 61

inches, and the MAD (mean absolute deviation) is 2 inches.

Select all the true statements. Make your selections bold.

A.

The median height of the sample must be between 59 and 63 inches.

B. Another random sample of 20 students is likely to have a mean between 57 and 65 inches.

C.

The mean height of these 20 students is likely to be the same as the mean height of all

students in the district.

D.

The mean height of these 20 students is likely to be the same as the mean height of a second

random sample of 20 students.

E.

Elena would be more likely to get an accurate estimate of the mean height of the population

by sampling 40 people instead of sampling 20 people.

Question

Mathematics

Abbie Jensen

19 October, 19:05

1. Elena would like to know the average height of seventh graders in her school district. She measures

the heights of everyone in a random sample of 20 students. The mean height of Elena's sample is 61

inches, and the MAD (mean absolute deviation) is 2 inches.

Select all the true statements. Make your selections bold.

A.

The median height of the sample must be between 59 and 63 inches.

B. Another random sample of 20 students is likely to have a mean between 57 and 65 inches.

C.

The mean height of these 20 students is likely to be the same as the mean height of all

students in the district.

D.

The mean height of these 20 students is likely to be the same as the mean height of a second

random sample of 20 students.

E.

Elena would be more likely to get an accurate estimate of the mean height of the population

by sampling 40 people instead of sampling 20 people.

+5

Answers (1)

Know the Answer?

Coach · Answer 1

A. The median height of the sample must be between 59 and 63 inches.

B. Another random sample of 20 students is likely to have a mean between 57 and 65 inches.

E. Elena would be more likely to get an accurate estimate of the mean height of the population by sampling 40 people instead of sampling 20 people.

Step-by-step explanation:

The mean absolute deviation shows the variation in a given data set. It can be determined by calculating the mean of the absolute value of the initial mean and each data set. It describes how spread out the data set are.

With respect to Elena's sampling, the mean absolute deviation is 2. This shows that there is little variation among the data set.

The estimate becomes more accurate if she increase the sample size. Thus options A, B and E are appropriate.