Standard Deviation Discrete Probability

The table represents the probability of guessing correct on a 5 question true-false quiz. Find the mean and the standard deviation.

• μ = .4; σ = 7.5

• μ = 2.5; σ = 1.1

• μ = 3; σ = 1.3

• μ = .1; σ = 0

The table above shows the number of cell phones per household in a small town. Find the standard deviation. Round to the nearest hundredth.

• 0.80

• 1.70

• 1.30

• 1.00

Is this a probability distribution?

• No

• Yes

The table above shows a television station's advertisement sales. The distribution of sales for one 24-hour day is given. Solve for the standard deviation. Round to the nearest hundredth.

• 45.81

• 266.2

• 16.30

• 0.20

Standard deviation describes what characteristic of a set of data?

• The number of data values.

• The expected data value.

• The spread of the data values from the mean.

• The range of the data values.

It is a number which describes the spread of the distribution.

The table above shows the number of cell phones per household in a small town. Find the standard deviation. Round to the nearest tenth.

The table above shows a television station's advertisement sales. The distribution of sales for one 24-hour day is given. Find the standard deviation for the length. Round to the nearest hundredth.

• 45.81

• 266.2

• 16.30

• 0.20

• Yes, because all of the probabilities are between 0 and 1 inclusive and the sum of all the probabilities is 1.
• No, all probabilities are not be between 0 and 1 inclusive
• No, the sum of all the probabilities is not 1.
• Yes, because the distribution is symmetric

Is this a probability distribution?

• No

• Yes