Answer: -1.33 .
Step-by-step explanation:
Formula to find the Z-score :

Given: Mean = 191 and Standard deviation = 21
Then , the z-score corresponding to the expected value of 163 will be :

Hence, the z score corresponding to selling 163 inhalers is -1.33 .
So what are we trying to find the reduced fraction or inverse operation
Answer: $216
Step-by-step explanation:
Hope it helped