THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
The time it takes to assemble an electronic component is normally distributed with a mean of 17.2 minutes and a standard deviation of 3.1 minutes.
-The probability is 95% that it will take at least how long to assemble a component?
A)12.7
B)11.7
C)12.1
D)11.1

Question

Quizplus · Accepted Answer

We need to find the value of x such that P(X ≥ x) = 0.95. Using the normal distribution table or a calculator, we can find the z-score corresponding to the 95th percentile, which is 1.645. Then we can solve for x using the formula x = μ + zσ, where μ = 17.2 and σ = 3.1. Substituting values, we get x = 17.2 + 1.645(3.1) ≈ 12.11. Rounding to one decimal place gives us the answer of 12.1 minutes.