Empirical Rule & Normal Distribution Practice

The shelf life of a particular dairy product is normally distributed with a mean of 12 days and a standard deviation of 3 days. About what percent of the products last between 12 and 15 days?

The mean GPA of students in a course at UGA is 3.2 with a standard deviation of 0.3. What percent of students in the course have a GPA between 2.9 and 3.8?

A town's average snowfall is 48 inches per year with a standard deviation of 6 inches. Using a Normal model, what percent of snow fall amounts will be between 42 and 54?

A company installs 5000 lightbulbs, each with an average life of 500 hours, a standard deviation of 100 hours, and a distribution that is approximately normal.

How many lightbulbs can be expected to last between 400 and 700 hours?

A grading scale is set up for 1000 students' test scores. It is assumed the scores are normally distributed with a mean score of 75 and a standard deviation of 15.

How many students will have a score between 45 and 75?

In the Olympics, the 100m sprint times are normally distributed with a mean of 10.5s and a standard deviation of 0.4s.

Out of 50 competitors, how many would you expect to record a time between 10.1 and 10.9 seconds?