Question

In pharmacologic research a variety of measurements are routinely monitored closely

for evidence of side eects of the medication under study. Suppose typical blood-

glucose levels are normally distributed with mean 90 mg/dL and standard deviation

38 mg/dL.

(a) Only values which in the higher 20% values are considered abnormal. How

high should the blood-glucose level be to be classied as abnormal?

(b) Another criteria to classify blood-glucose level as abnormal is if the measure-

ment is greater than 138 mg/dL. What is the probability that three indepen-

dently selected individuals are all classied as abnormal?

Answer 1

Let X be the blood-glucose levels.

a) The value of x such that the probability of the blood-glucose levels is greater than x is 0.20 given by:

That is

### By using Z table

b) The probability that three independently selected individuals are all classied as abnormal is given by

### using Z table