normalcdf(a, b, μ, σ) In Excel, P(a \leq X \leq b) is computed with the formula =NORMDIST(b, μ, σ 1)-NORMDIST(a, μ, σ 1) Alternatively, you could use the Numerical integration utility on this Website: Enter the formula Y1=(1/(0.5(2*pi;)^0.5))e^(-(X-50)...