"quantity"exercise: Common Probability Distributions

下载正保会计网校APP 订阅最新报考消息

来源: 正保会计网校编辑：小鞠橘桔 2020/09/27 09:16:31　字体：大小

学习是一个不断积累的过程，每天学习一点，每天进步一点！为了帮助大家更高效地备考2021年CFA考试，正保会计网校每日为大家上新CFA习题供大家练习。让网校与您一起高效备考2021年CFA考试，梦想成真！

Questions 1:

When flipping three coins simultaneously, the number of outcomes that contain at least two heads is most likely:

A、 eight.

B 、four.

C、 three.

Questions 2:

A company has an unsecured line of credit and needs to maintain its EBITto-interest coverage ratio greater than 2.0. Its EBIT is estimated to be between $36 million and $48 million, with all values equally likely. If the forecasted interest charge for the year is $20 million, the probability that EBIT/interest will be more than 2.0 is closest to:

A、 61.5%.

B、 33.3%.

C 、66.7%

View answer resolution

【Answer to question 1】B

【analysis】

B is correct. The number of outcomes having at least two heads is four, as indicated in the following table.

捕获1 A is incorrect. The outcome of at least one head is calculated instead.

C is incorrect. The outcome of (H,H,H) is not counted.

【Answer to question 2】C

【analysis】

C is correct. The EBIT-to-interest ratio is equal to 2.0 when the EBIT is $40 million. Given that the values between $36 million and $48 million are equally likely, the probability of the ratio being equal to or less than 2.0 is 33.3% (= [$40 million – $36 million]/[$48 million – $36 million]). Consequently, the probability of the ratio being greater than 2.0 is 66.7% (i.e., 1 – Probability of the ratio being equal to or less than 2.0). A is incorrect. This treats the distribution as discrete with increments in $1M.

捕获3 B is incorrect. This is the probability of the ratio being equal to or less than 2.0. Common Probability Distributions