Answer: 12.51%
Explanation: Probability of normal = 100 - (35+10)=55%
Expected return = Respective return*Respective Probability
= (22*0.1)+(9*0.55)+(-14*0.35) = 2.25%
When
(a) Return = 22% , Probability = 0.1
![\therefore Probability* (Return-Expected Return)^2](https://img.qammunity.org/2020/formulas/business/college/1m1mwp4zgo9ourdwua50orjwqn582ub7h0.png)
![0.1*(22-2.25)^2=39.006](https://img.qammunity.org/2020/formulas/business/college/djayknxbfxnl0eewpmky4x3pzyih2wm4db.png)
(b) Return = 9%, Probability = 0.55
![\therefore Probability* (Return-Expected Return)^2](https://img.qammunity.org/2020/formulas/business/college/1m1mwp4zgo9ourdwua50orjwqn582ub7h0.png)
![0.55*(9-2.25)^2=25.05](https://img.qammunity.org/2020/formulas/business/college/tby2xhxu62u3aildir4yhc8ulf45f164ik.png)
(b) Return = -14%, Probability = 0.35
![\therefore Probability* (Return-Expected Return)^2](https://img.qammunity.org/2020/formulas/business/college/1m1mwp4zgo9ourdwua50orjwqn582ub7h0.png)
![0.35*(-14-2.25)^2=92.42](https://img.qammunity.org/2020/formulas/business/college/2q66b92037no7g5ynhqf4gq5391x2wk1zd.png)
Total=156.48%
![Standard deviation= [Total Probability * (Return-Expected Return)^(2)/ Total probability]^(1/2)](https://img.qammunity.org/2020/formulas/business/college/vybq2xg49qgzmbcv0zzdu6vk1hzcizrev2.png)
Standard deviation = 12.51%