Probability Distribution Expected Value

• 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

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

The following table presents a probability distribution for the number of pets each family has in a certain neighborhood. Find the probability that a randomly selected family has 1 or 2 pets.

• 0.2

• 0.4

• 0.1

• 0.5

Is this a probability distribution?

• No

• Yes

The table represents the probability of guessing correct on a 5 question true-false quiz.  Find the probability for at least 4 questions correct.

• .03125

• .15625

• .3125

• .1875

• Discrete
• Continuous

• Discrete
• Continuous

Is this a valid probability distribution?

• 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 valid 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.

Is this a valid probability distribution?

• 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