The scores for the Algebra 2 CFE are normally distributed with a mean score of 43 and a standard deviation of 3.8. If you scored 47 on the test, what percentage of test takers scored lower than you? Do not round your answer. [percent]

Respuesta :

Answer:

Step-by-step explanation:

Let x be the random variable representing the scores for the Algebra 2 CFE. Since they are normally distributed and the population mean and population standard deviation are known, we would apply the formula,

z = (x - µ)/σ

Where

x = sample mean

µ = population mean

σ = standard deviation

From the information given,

µ = 43

σ = 3.8

the probability that a test taker scores less than 47 is expressed as

P(x ≤ 47)

For x = 47

z = (47 - 43)/3.8 = 1.05

Looking at the normal distribution table, the probability corresponding to the area to the left of the z score is 0.85314

The percentage of test takers that would score lesser than you is

0.85314 × 100 = 85.314%