Statistics Spring 2023 Practice Final Exam

Which descriptions are true for a binomial distribution?

• the probability of success must be the same for each event

• the probability for each event must be 0.5

• there can be only two possible outcomes

• The probabilities must add to 1

• each trial must be independent

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CCSS.HSS.MD.A.3

CCSS.HSS.MD.A.4

In a certain town, 75% of all drivers are insured. What is the expected number of insured drivers present in a group of 200 randomly selected townspeople?

• 75

• 150

• 175

• 125

In a certain town, 90% of the people drive without ever looking at their phones. In a group of 200 randomly selected citizens, what is the variance?

• 18

• 4.24

• 180

• 90

At a certain restaurant, there is a 70% probability that the flowers on your table will be yellow. If you are there with a group that is occupying 6 tables, what is the probability that 5 of the tables will have yellow flowers?

• 70%

• 70.6 %

• 30.3 %

• 5.0 %

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.

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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

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CCSS.HSS.MD.A.2

The table above shows a television station's advertisement sales. The distribution of sales for one 24-hour day is given. What is the probability of sales between 15 and 30? Round to the nearest hundredth.

• .134

• .08

• .92

• .786

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

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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 probability for at least 4 questions correct.

• .03125
• .15625
• .3125
• .1875

Tags

CCSS.HSS.MD.A.3

CCSS.HSS.MD.A.4