Question

All students in school took a physical fitness test. Four students want to estimate the mean score for the school. To do this, they each randomly chose 5 schoolmates and recorded their scores. The samples are shown in the table. Do not round your answers

Answer 1

The Solution:

Given:

Part (a):

Find the sample means by the 4 students.

Student 1:

`sample\text{ mean}=(60+20+30+40+20)/(5)=(170)/(5)=34`

Student 2:

`Sample\text{ mean}=(30+70+30+20+20)/(5)=(170)/(5)=34`

Student 3:

`sample\text{ mean}=(20+40+40+60+20)/(5)=(180)/(5)=36`

Student 4:

`Sample\text{ mean}=(40+50+50+20+30)/(5)=(190)/(5)=38`

Part (b):

Find the range of the sample means.

`Range=largest\text{ mean}-smallest\text{ mean}`
`Range=38-34=4`

Part (c):

Thus, the correct answers are [options B and D]