Summative Test in Statistics & Probability11

The mean life of a tire is 30,000 km. The standard deviation is 2000 km. Then, 68% of all tires will have a life between ___________ km and __________ km. (Remember to draw a curve with the values to help you.)

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? (Remember to draw a curve with the values to help you.)

Which interval shows 95% of the data given a mean of 15 and a standard deviation of 3? (Remember to draw a curve with the values to help you.)

Which interval shows 68% of the data given a mean of 15 and a standard deviation of 3? (Remember to draw a curve with the values to help you.)

Which interval shows 99.7% of the data given a mean of 15 and a standard deviation of 3? (Remember to draw a curve with the values to help you.)

What percent of people within 1 standard deviation of the mean?

• 99.7%

• 68%

• 34

• 95

What is the total area in the distribution under the normal curve?

• 0

• 1

• 2

• 3

What percent of people within 2 standard deviations of the mean?

• 99.7%

• 68%

• 34

• 95

When labeling the axis for a normal distribution curve, the notation σ is used to represent standard deviation. What is this Greek letter σ called?

• Omega

• Lowercase Sigma

• Delta

• Lowercase Omega

The Empirical (68-95-99.7) Rule can be applied only if data is ....

• Normally Distributed

• Skewed

• Uniform

• Symmetric