Question

Scores on a standardized test are approximately normally distributed with a mean of 480 and a standard deviation of 90. A student has a score of 600. What percentile is the student's score closest to

Answer 1

Answer: the student's score closest to 91 percentile.

Explanation:

Since the scores on the standardized test are approximately normally distributed, we would apply the formula for normal distribution which is expressed as

z = (x - µ)/σ

Where

x = test scores.

µ = mean score

σ = standard deviation

From the information given,

µ = 480

σ = 90

If a student has a score of 600, then x = 600

For x = 600,

z = (600 - 480)/90 = 1.33

Looking at the normal distribution table, the probability corresponding to the z score is 0.91

the student's score closest to 91 percentile.