probability Distributions

Which one of the following is a discrete random variable?

• Sam's height

• Sam weight

• Time Sam's runs the 110 m hurdles

• Amount of Sam's brothers and sisters

Is this a probability distribution?

• No, the sum of p(x) does not equal 1.

• Yes, all p(x) are between 0 and 1.

• No, all p(x) are not between 0 and 1.

• Yes, the sum p(x) is 1.

Tags

CCSS.HSS.MD.A.3

CCSS.HSS.MD.A.4

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

• 31.8

• 15.68

• 0.20

• 1.00

Tags

CCSS.HSS.MD.A.2

Classify: The numbers of cheeseburgers a fast-food restaurant serves each day

• Discrete

• Continuous

Classify: The time it takes for a light bulb to burn out.

• Discrete

• Continuous

Is this a probability distribution?

• No

• Yes

Tags

CCSS.HSS.MD.A.3

CCSS.HSS.MD.A.4

Is this a probability distribution?

• No
• Yes

Tags

CCSS.HSS.MD.A.3

CCSS.HSS.MD.A.4

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

• 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

Tags

CCSS.HSS.MD.A.3

CCSS.HSS.MD.A.4

A marketing survey compiled data on the number of cars in households.  If X = the number of cars in a randomly selected household, and we omit the rare cases of more than 5 cars, then X has the following probability distribution: 
X           0          1          2          3           4           5    
P(X)   0.24    0.37    0.20    0.11    0.05     0.03
What is the probability that a randomly chosen household has at least two cars?

• 0.20
• 0.29
• 0.39
• 0.61

Tags

CCSS.HSS.MD.A.3

CCSS.HSS.MD.A.4