At a local manufacturing plant, employees must complete new machine set-ups within 30 minutes. New machine set-up times can be described by a Normal model with a mean of 22 minutes and a standard deviation of four minutes.
a. What percent of new machine set-ups take more than 30 minutes?
b. The typical worker needs five minutes to adjust to their surroundings before beginning their duties. What percent of new machine set-ups are completed within 25 minutes to allow for this?

Question

Quizplus · Accepted Answer

The Answer is a. P(x > 30) = P a. P(x > 30) = P = P(z > 2.00) = 0.0228 = 2.28% b. P(x ≤ 25) = P = P(z ≤ 0.75) = 0.7734

= P(z > 2.00) = 0.0228 = 2.28%
b. P(x ≤ 25) = P a. P(x > 30) = P = P(z > 2.00) = 0.0228 = 2.28% b. P(x ≤ 25) = P = P(z ≤ 0.75) = 0.7734

= P(z ≤ 0.75) = 0.7734

At a Local Manufacturing Plant, Employees Must Complete New Machine