Question

The average mark of candidate in an aptitude test was 128.5 with a standard deviation of 8.2. Three scores extracted from the test are 148, 102,152. What is the average of the extracted scores t hat are extreme values (outliers)?

Answer 1

Explanation:

Given that : The average marks of candidates in an aptitude test was 128.5 with a standard deviation of 8.2. Three scores extracted from the test are; 148, 102 and 152.

The objective here is to determine the average of the extracted scores that are the extreme values (outliers)

NOW:

The average marks of candidates in an aptitude test was 128.5

i.e the Mean = 128.5

Standard Deviation = 8.2

outlier will be outsides;

then the range will be Mean ± 3 × SD

= 128.5 ± 8.2 × 3

= 128.5 ± 24.6

Range is ( 103.9 , 153.1)

102 is outside this range

Hence, the average of the extracted scores that are extreme values (outliers) will be 102 only