Reading 8: Probability Concepts-LOS f, (Part 3)习题精选 2010, employees, face, company, interpret

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Session 2: Quantitative Methods: Basic Concepts
Reading 8: Probability Concepts

LOS f, (Part 3): Calculate and interpret a joint probability of any number of independent events.

 

 

 

A very large company has equal amounts of male and female employees. If a random sample of four employees is selected, what is the probability that all four employees selected are female?

A) 0.0256

B) 0.0625.

C) 0.1600

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Which of the following is a joint probability? The probability that a:

A) stock pays a dividend and splits next year.

B) company merges with another firm next year.

C) stock increases in value after an increase in interest rates has occurred.

bmaggie

Which of the following is a joint probability? The probability that a:

A) stock pays a dividend and splits next year.

B) company merges with another firm next year.

C) stock increases in value after an increase in interest rates has occurred.

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A joint probability applies to two events that both must occur.

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There is a 30% probability of rain this afternoon. There is a 10% probability of having an umbrella if it rains. What is the chance of it raining and having an umbrella?

A) 40%.

B) 33%.

C) 3%.

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There is a 30% probability of rain this afternoon. There is a 10% probability of having an umbrella if it rains. What is the chance of it raining and having an umbrella?

A) 40%.

B) 33%.

C) 3%.

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P(A) = 0.30. P(B | A) = 0.10. P(AB) = (0.30)(0.10) = 0.03 or 3%.

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A bond portfolio consists of four BB-rated bonds. Each has a probability of default of 24% and these probabilities are independent. What are the probabilities of all the bonds defaulting and the probability of all the bonds not defaulting, respectively?

A) 0.96000; 0.04000.

B) 0.00332; 0.33360.

C) 0.04000; 0.96000.

bmaggie

A bond portfolio consists of four BB-rated bonds. Each has a probability of default of 24% and these probabilities are independent. What are the probabilities of all the bonds defaulting and the probability of all the bonds not defaulting, respectively?

A) 0.96000; 0.04000.

B) 0.00332; 0.33360.

C) 0.04000; 0.96000.

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For the four independent events where the probability is the same for each, the probability of all defaulting is (0.24)⁴. The probability of all not defaulting is (1 ? 0.24)⁴.

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If two fair coins are flipped and two fair six-sided dice are rolled, all at the same time, what is the probability of ending up with two heads (on the coins) and two sixes (on the dice)?

A) 0.8333.

B) 0.4167.

C) 0.0069.

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If two fair coins are flipped and two fair six-sided dice are rolled, all at the same time, what is the probability of ending up with two heads (on the coins) and two sixes (on the dice)?

A) 0.8333.

B) 0.4167.

C) 0.0069.

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For the four independent events defined here, the probability of the specified outcome is 0.5000 × 0.5000 × 0.1667 × 0.1667 = 0.0069.

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If two events are independent, the probability that they both will occur is:

A) Cannot be determined from the information given.

B) 0.50.

C) 0.00.