AP Statistics Chapter 6 Test

John maintains two separate lines of lobster traps in Penobscot Bay. The East Bay trap produces a mean of 12 pounds of lobsters per day with a standard deviation of 7 pounds. The West Bay trap produces a mean of 10 pounds of lobsters a day with a standard deviation of 4.5 pounds. The weight of lobsters produced by each trap is independent of the other. Which of the following are the mean and approximate standard deviation of the total weight of lobsters John traps in a day?

• Mean = 22 pounds; Standard deviation = 5.75 pounds

• Mean = 22 pounds; Standard deviation = 8.32 pounds

• Mean = 22 pounds; Standard deviation = 11.50 pounds

• Mean 11 pounds; Standard deviation = 11.50 pounds

• Mean = 11 pounds; Standard deviation = 8.32 pounds

At a carnival, a particular game requires the player to spin a wheel. When a child plays, the game operator allows them to continue to spin the wheel until they win a prize. Define X = the number of spins a child takes until they win a prize. Which, if any, of the following requirements for X to be a binomial random variable is violated in this setting?

Which of the following is the best interpretation of the expected value E(C) that you found in question 6.

• If the company insures 10 cars of this model, they know they will incur 10×E(C) in costs.

• The maximum cost to the company for insuring this car model is E(C) per car.

• The company must insure at least E(C) of these cars to make a profit.

• If the company insures a large number of these cars, they can expect the average cost per car to be approximately E(C).

• If the company insures a large number of these cars, they can expect the variability in cost per car to average approximately E(C).

• A

• B

• C

• D

• E

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.

Is this a probability distribution?

• No

• Yes

An inspector examines a large shipment of several thousand laser pointers by randomly selecting and then inspecting 6 laser pointers. Suppose that 1% of the laser points are defective. Which one of the following expressions describes the probability that exactly one of the six laser pointers is defective?

• (9) (0.01) (0.99)

• (9)(0.01)(0.99)*

• (0.01)6

• (0.99) (0.01)

• (0.99)³ (0.01)

• A

• B

• C

• D

• E

• A

• B

• C

• D

• E

• A

• B

• C

• D

• E