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
问题描述：
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!
答
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=≈0.0375②[(2% ...