題組內容
5. Ten million dollars are invested in long-term business bonds by Percival Hygiene. The annual standard deviation of this bond portfolio is 10%, while the predicted annual rate of return is 9%. Percival's financial advisor, Amanda Reckonwith, suggests that Percival think about purchasing an index fund that closely resembles the Standard & Poor's 500 Index. The index has an expected return of 14%, and its standard deviation is 16%.
(a) (10%) Suppose Percival puts all his money in a combination of the index fund and Treasury bills. Can he thereby improve his expected rate of return without changing the risk of his portfolio? The Treasury bill yield is \( 6\% \).