Explanation:
The formula to compute the expected rate of return under the CAPM method is shown below:
Expected rate of return = Risk-free rate of return + Beta × (Market rate of return - Risk-free rate of return)
where,
(Market rate of return - Risk-free rate of return) is also known as market risk premium
So, the first equation is
0.123 = risk free rate of return + 1.05 × market risk premium
And, the other equation is
0.118 = risk free rate of return + 0.90 × market risk premium
Now if we equate this above equation
So,
0.005 = 0.15 × market risk premium
So, the market risk premium is
= 0.0333
Now place the market risk premium value in any of the above equation
0.123 = Risk free rate of return + 1.05 × 0.0333
So, the risk free rate of return is 8.80%
And, the expected rate of return is
= 3.33% + 8.80%
= 12.13%