Scores on the ACT college entrance exam follow a bell-shaped distribution with mean 21 and standard deviation 5. Wayne’s standardized score on the ACT was 0.6 What was Wayne’s actual ACT score?

a. 3

b. 13

c. 16

d. 18

e. 24

Short Answer

Expert verified

The correct option is (d)18

Step by step solution

01

Given information

Mean =21

Standard Deviation =5

Standardized score is =-0.6

02

Concept

The formula used:Z=xμσ

03

Calculation

Z=xμσZ×σ=xμZ×σ+μ=xx=μ+Z×σ=21+(0.6)×5=213x=18

Hence, the correct option is (d)

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