Question

You work for a pharmacy and monthly sales of asthma inhalers in your pharmacy follows a normal distribution with a mean of 191 inhalers per month and a standard deviation of 21 due to a storm the next shipment of inhalers did not arrive. The pharmacy only has 163 inhalers currently in stock and available to sell for the current month. What is the z score corresponding to selling 163 inhalers?

Answer 1

Answer: -1.33 .

Step-by-step explanation:

Formula to find the Z-score :

$Z=\dfrac{\text{Expected value - Mean}}{\text{Standard deviation}}$

Given: Mean = 191  and Standard deviation = 21

Then , the z-score corresponding to the expected value of 163 will be :

$Z=\dfrac{163-191}{21}\\\\=\dfrac{-28}{21}\approx-1.33$

Hence, the z score corresponding to selling 163 inhalers is -1.33 .