① [(−3% − 5.4%)^2×0.1 + (3% − 5.4%)^2×0.3 + (7% − 5.4%)^2×0.4 + (10% − 5.4%)^2×0.2 ]^1/2②[(2% − 9.4%)^2×0.1+ (4% − 9.4%)^2×0.3 + (10% − 9.4%)^2×0.4 + (20% − 9.4%)^2×0.2 ]^1/2注：但

① [(−3% − 5.4%)^2×0.1 + (3% − 5.4%)^2×0.3 + (7% − 5.4%)^2×0.4 + (10% − 5.4%)^2×0.2 ]^1/2②[(2% − 9.4%)^2×0.1+ (4% − 9.4%)^2×0.3 + (10% − 9.4%)^2×0.4 + (20% − 9.4%)^2×0.2 ]^1/2注：但
① [(−3% − 5.4%)^2×0.1 + (3% − 5.4%)^2×0.3 + (7% − 5.4%)^2×0.4 + (10% − 5.4%)^2×0.2 ]^1/2
②[(2% − 9.4%)^2×0.1+ (4% − 9.4%)^2×0.3 + (10% − 9.4%)^2×0.4 + (20% − 9.4%)^2×0.2 ]^1/2
注：但望能体谅!

① [(−3% − 5.4%)^2×0.1 + (3% − 5.4%)^2×0.3 + (7% − 5.4%)^2×0.4 + (10% − 5.4%)^2×0.2 ]^1/2②[(2% − 9.4%)^2×0.1+ (4% − 9.4%)^2×0.3 + (10% − 9.4%)^2×0.4 + (20% − 9.4%)^2×0.2 ]^1/2注：但
① [(−3% − 5.4%)^2×0.1 + (3% − 5.4%)^2×0.3 + (7% − 5.4%)^2×0.4 + (10% − 5.4%)^2×0.2 ]^1/2
=[0.0007056+0.0001728+0.0001024+0.0004232]^1/2
=0.001404^1/2=≈0.0375
②[(2% − 9.4%)^2×0.1+ (4% − 9.4%)^2×0.3 + (10% − 9.4%)^2×0.4 + (20% − 9.4%)^2×0.2 ]^1/2
=[0.0005476+0.0008748+0.0000144+0.0022472]^1/2
=0.003684^1/2≈0.06070