Question

The red blood cell counts​ (in millions of cells per​ microliter) for a population of adult males can be approximated by a normal​ distribution, with a mean of million cells per microliter and a standard deviation of million cells per microliter. ​(a) What is the minimum red blood cell count that can be in the top ​% of​ counts? ​(b) What is the maximum red blood cell count that can be in the bottom ​% of​ counts?

Answer 1

(a) Minimum red blood cells 5.744 million cells per micro liter

(b) Maximum red blood cells 5.068 million cells per micro liter.

Explanation:

Z-score formula is =
`(x-u)/(Standard deviation)`

Z-score =
`(x-5.5)/(0.4)`

The value of z-score is 0.61 so then x will be;

x = 5.744

The minimum red blood cells count that can in top is 27% of count which is 5.744 million cells per micro liter.

Z-score =
`(x-5.5)/(0.4)`

The value of z-score is 0.14 so then x will be;

x = 5.068

The maximum red blood cells count that can be in top is 14% of count which is 5.068 million cells per micro liter.