At a cell phone assembly plant, 83% of the cell phone keypads pass inspection. A random sample of 192 keypads is analysed. Find the probability that less than 86% of the sample keypads pass inspection
A)0.8962
B)0.1335
C)0.8665
D)0.1038

Question

Quizplus · Accepted Answer

The sample proportion follows a normal distribution with mean 0.83 and standard deviation calculated using the formula for the standard deviation of a sample proportion. Using the z-score formula, we find the probability that less than 86% of the sample keypads pass inspection.

At a Cell Phone Assembly Plant, 83% of the Cell