In: Finance
A pension fund manager is considering three mutual funds. The
first is a stock fund, the second is a long-term government and
corporate bond fund, and the third is a T-bill money market fund
that yields a sure rate of 5.3%. The probability distributions of
the risky funds are:   
| Expected Return | Standard Deviation | |||
| Stock fund (S) | 14 | % | 43 | % | 
| Bond fund (B) | 7 | % | 37 | % | 
The correlation between the fund returns is .0459.
Suppose now that your portfolio must yield an expected return of
12% and be efficient, that is, on the best feasible CAL.
a. What is the standard deviation of your
portfolio? (Do not round intermediate calculations. Round
your answer to 2 decimal places.)
Standard deviation
            %
b-1. What is the proportion invested in the T-bill fund? (Do not round intermediate calculations. Round your answer to 2 decimal places.)
Proportion invested in the T-bill fund
            %
b-2. What is the proportion invested in each of
the two risky funds? (Do not round intermediate
calculations. Round your answers to 2 decimal places.)
| Proportion Invested | |
| Stocks | % | 
| Bonds | % | 
To find the fraction of wealth to invest in stock 1 that will result in the risky portfolio with
the maximum Sharpe ratio the following formula to determine the weight of debt in risky portfolio should be used

| Where | ||
| Bond | E[R(d)]= | 7.00% | 
| Stock | E[R(e)]= | 14.00% | 
| Bond | Stdev[R(d)]= | 37.00% | 
| Stock | Stdev[R(e)]= | 43.00% | 
| Var[R(d)]= | 0.1369 | |
| Var[R(e)]= | 0.1849 | |
| T bil | Rf= | 5.30% | 
| Correl | Corr(Re,Rd)= | 0.0459 | 
| Covar | Cov(Re,Rd)= | 0.0073 | 
| Therefore W(*d)= | 0.1755 | |
| W(*e)=(1-W(*d))= | 0.8245 | |
| Expected return of risky portfolio= | 12.77% | |
| Risky portfolio std dev = | 36.34% | |

| Desired return= | 12% | 
| = tbill return*proportion invested in tbill+risky portfolio return *(1-return*proportion invested in tbill) | 
| 0.12=0.053*Proportion invested in Tbill+0.1277*(1-Proportion invested in Tbill) | 
| Proportion invested in Tbill (answer b.1)= (0.1277-0.12)/(0.1277-0.053) | 
| =0.1 | 
| proportion invested in risky portfolio = 1-*proportion invested in tbill | 
| =0.9 | 
| Proportion invested in stock fund (answer b.2)=proportion invested in risky portfolio *weight of stock fund | 
| =0.74 | 
| Proportion invested in bond fund (answer b.2)=proportion invested in risky portfolio *weight of bond fund | 
| =0.1579 | 
| std dev of portfolio (answer a) = std of risky portfolio*proportion invested in risky portfolio | 
| 0.9*0.3634=32.71% |