Business Statistics - Numerical Descriptive Measures

The empirical rule says that approximately what percentage of the values would be within 2 standard deviations of the mean in a bell-shaped set of data?

• 95%
• 68%
• 50%
• 97.7%
• 100%

A statistics student made the following grades on 5 tests: 84, 78, 88, 78, and 72.

What is the mean grade?

• 78
• 80
• 72
• 84
• 88

A statistics student made the following grades on 5 tests: 84, 78, 88, 78, and 72.

What is the median grade?

• 88
• 72
• 78
• 80
• 82

A statistics student made the following grades on 5 tests: 84, 78, 88, 78, and 72.
What is the mode?

• 78
• 80
• 88
• 84
• 82

A commuter travels many miles to work each morning. She has timed this trip 5 times

during the last month. The time (in minutes) required to make this trip was 44, 39, 41,

35, and 41. The mean time required for this trip was 40 minutes.

What is the variance for this sample data?

• 8.8
• 11
• 0
• 3
• -2

A commuter travels many miles to work each morning. She has timed this trip 5 times

during the last month. The time (in minutes) required to make this trip was 44, 39, 41,

35, and 41. The mean time required for this trip was 40 minutes.

What is the standard deviation for this sample data?

• 3.32
• 2.97
• 1.73
• 11
• -1.4

According to Chebyshev's Theorem how many values in a data set will be within 2 standard deviations of the mean?

• At least 75%
• At least 68%
• At least 95%
• At least 89%
• At least 99%