宇同学2022-12-30 21:56:22

Suppose the prospects for recovering principal for a defaulted bond issue depend on which of two economic scenarios prevails. Scenario 1 has probability 0.75 and will result in recovery of $0.90 per $1 principal value with probability 0.45, orin recovery of $0.80 per $1 principal value with probability 0.55. Scenario 2 has probability 0.25 and will result in recovery of $0.50 per $1 principal value with probability 0.85, or in recovery of $0.40 per $1 principal value with probability 0.15. A. Compute the probability of each of the four possible recovery amounts: $0.90, $0.80, $0.50, and $0.40. B. Compute the expected recovery, given the first scenario. C. Compute the expected recovery, given the second scenario. D. Compute the expected recovery. E. Graph the information in a probability tree diagram. 图为我做题的过程，B、C、D这三问题，算出来的结果跟答案不一样？我到底错在哪个地方？