Answer: 11.27%
Explanation:
First calculate the portfolio beta which is a weighted average of the individual betas;
= (260,000/4,590,000 * 1.50) + (360,000/4,590,000 * -0.5) + (1,220,000/4,590,000 * 1.25) + (2,750,000/4,590,000 * 0.75)
= 0.827342
Use CAPM to calculate the required return ;
= risk free rate + beta ( market return - risk free rate)
= 3% + 0.827342(13% - 3%)
= 0.1127342
= 11.27%