Question

The monthly amount spent on stationery in a large company has a normal distribution with mean R2500 and standard deviation R150. How much should the company budget for stationery if the chance of exceeding the budget has to be only 2.5%?

Answer 1

$$P(X>x)=1-P(Z\le \dfrac{x-2500}{150})=0.025$$

$$\dfrac{x-2500}{150}=1.96$$

$$x=2500+150(1.96)$$

$$x=R2794$$