Question

LSAT test scores are normally distributed with a mean of 152 and a standard deviation of 10. Find the probability that a randomly chosen test-taker will score 142 or lower. (Round your answer to four decimal places.)

Answer 1

the probability that a randomly chosen test-taker will score 142 or lower = 0.8643

Explanation:

We are given;

Data point; x = 142

Mean; μ = 153

Standard deviation; σ = 10

So,let's find the z-score using;

z = (x - μ)/σ

z = (142 - 153)/10

z = -1.1

From the z-distribution table attached, the probability is;

P(z < -1.1) = 1 - 0.13567 ≈ 0.8643