In a class of 25 one student receives a score of 100 on a te

In a class of 25, one student receives a score of 100 on a test. The grades are distributed normally, with a mean of 78 and a standard deviation of 5. Do you think the student\'s score is an outlier? Explain.

Set 1

Set 2

Set 3

1

5

5

10

7

6

5

7

9

19

7

1

2

4

1

7

11

5

1

7

11

7

7

1

2

7

10

10

9

4

6

7

2

9

7

8

Solution

In a class of 25, one student receives a score of 100 on a test. The grades are distributed normally, with a mean of 78 and a standard deviation of 5. Do you think the student\'s score is an outlier? Explain.

Standard error = s/sqrt(n) = 5/sqrt(25) =1

Z value for 100, ( 100-78)/1 =22

The calculated z value 22 > 3, we conclude that student\'s score is an outlier