Question

On a final examination in mathematics, the mean was 76 and the standard deviation was 5. Determine the

standard score of a student who received a score of 88 assuming the scores are normally distributed

Answer 1

Solution

Population mean $\mu=76$

Standard deviation $\sigma=5$

$X=88$

$Z=\dfrac{X-\mu}{\sigma}=\dfrac{88-76}{5}$

$Z=2.4$

From normal distribution tables

P(Z of 2.4) $=0.99180$

or

$99.18\%$