A line up for tickets to a local concert has a mean waiting time of 20 minutes with a standard deviation of 4 minutes. If 2000 ticket buyers were in line, how many of them would expect to wait less than 16 minutes?

On a recent math test, the mean score was 75 and the standard deviation was 5. Approximately what percent of the scores fall in the range of 65 to 80?

In an Oreo factory, the mean mass of a cookie is given as 40g. For quality control, the standard deviation is 2g. If 10,000 cookies were produced, how many cookies are within the range of 38 to 42 grams?

The speeds of cars on the highway have a mean of 65 mph with a standard deviation of 5 mph. What percentage of cars averaged less than 70 mph?

The speeds of 8000 cars on the highway have a mean of 65 mph with a standard deviation of 5 mph. If a police car stopped cars that were going more than 75 mph, how many cars would they stop?

 $z=\frac{x-\mu}{\sigma}$  What does  $\sigma$  stand for?

 $z=\frac{x-\mu}{\sigma}$  What does x stand for?

In a normally distributed set of data, if the z score is 2, what can you say about the value?

What percent is within one central standard deviation of the mean?

Use the following information and the Empirical Rule to estimate the answer.

The ages of golfers are normally distributed, with a mean of 38 and a standard deviation of 4.

There are 500 golf members at the Mathy Country Club. How many are younger than 34?