In: Finance
1). Expected return (Er) = sum of [probability*return]
Expected return of A (ErA) = (0.6*3%) + (0.4*15%) = 7.80%
Expected return of B (ErB) = (0.6*6.50%) + (0.4*6.50%) = 6.50%
2). Standard deviation (SD) = variance^0.5 where
variance (V) = sum of [probability*(return - Er)^2]
Variance of A (VA) = 0.6*(3%-7.80%)^2 + 0.4*(15%-7.80%)^2 = 0.003456
Variance of B (VB) = 0 since it gives same return for both bear and bull states.
SDA = 0.003456*0.5 = 5.88%
SDB = 0%
3). Variance of A (VA) = 0.003456 (Calculated above)
VB = 0 (since return remains same in both states)
4). Coefficient of variation (CoV) = SD/Er
CoV for A = 5.88%/7.80% = 0.7537
CoV for B = 0/6.50% = 0.0000
5). Portfolio expected return = sum of [weight of asset*expected return of asset]
weight of asset = amount invested in asset/total amount invested
weight of A (wA) = 2,500/(2,500+3,500) = 41.67%
weight of B (wB) = 3,500/(2,500+3,500) = 58.33%
Portfolio expected return = (41.67%*7.80%) + (58.33%*6.50%) = 7.04%
6). Portfolio standard deviation = [(wA*SDA)^2 + (wB*SDB)^2 + (2*wA*wB*SDA*SDB*correlation)]^0.5
= [(41.67%*5.88%)^2 + (58.33%*0%)^2 + (2*41.67%*58.33%*5.88%*0%*0.4)]^0.5 = 2.45%