Assume that you manage a risky portfolio with an expected rate of return of $17\%$ and a standard deviation of $27\%.$ The T$-$bill rate is $7\%.$

Your risky portfolio includes the following investments in the given proportions:

Your client decides to invest in your risky portfolio a proportion $(y)$ of his total investment budget with the remainder in a T$-$bill money

market fund so that his overall portfolio will have an expected rate of return of $15\%.$

Required:

a$.$ What is the proportion $y?($Round your answer to $1$ decimal place.$)$

Proportion y

$\%$

Please explain.