Question

A pharmaceutical testing company wants to test a new cholesterol drug. The average cholesterol of the target population is 200 mg and they have a standard deviation of 25 mg. The company wished to test a sample of people who fall between 1.5 and 3​ z-scores above the mean. Into what range must a​ candidate's cholesterol level be in order for the candidate to be included in the​ study?

Answer 1

The required range is 237.5 to 275.

Explanation:

Consider the provided information.

The average cholesterol of the target population is 200 mg and they have a standard deviation of 25 mg.

The the value of μ = 200 and the
`\sigma=25`

The company wished to test a sample of people who fall between 1.5 and 3​ z-scores above the mean.

Let the value of z is 1.5.

Now use the z score formula:
`z=((x -\mu))/(\sigma)`

Substitute the respective values in the above formula.

`1.5=((x -200))/(25)`

`37.5=x -200`

`237.5=x`

Now let the value of z is 3.

Substitute the respective values in the z score formula.

`3=((x -200))/(25)`

`75=x -200`

`275=x`

Hence, the required range is 237.5 to 275.