What percent of quality-control results will fall outside of plus or minus 2 standard deviations from the mean?

Question

Quizplus · Accepted Answer

According to the normal distribution, about 68% of data falls within plus or minus 1 standard deviation from the mean, about 95% falls within plus or minus 2 standard deviations from the mean, and about 99.7% falls within plus or minus 3 standard deviations from the mean. Therefore, approximately 5% of quality-control results will fall outside of plus or minus 2 standard deviations from the mean.

What Percent of Quality-Control Results Will Fall Outside of Plus