# Calculate NORM.S.INV(0.30) and NORM.S.INV(0.70).

## Question:

Calculate NORM.S.INV(0.30) and NORM.S.INV(0.70).

## Z score:

Z score of a random Variable x is obtained using formula{eq}Z =\frac{x-\mu}{\sigma} {/eq}

Where z follows standard normal distribution with mean 0 and standard deviation 1.

{eq}f(z)=\frac{1}{\sqrt{2\pi}}e^{-\frac{z^2}{2}} \qquad -\infty \leq z\leq \infty {/eq}

Z value of a cumulative probability can be obtained using Ms Excel formula NORM.S.INV(Probability) e.g NORM.S.INV(0.5)= 0

So we have NORM.S.INV(0.30)=-0.524

NORM.S.INV(0.70)=0.5244