In: Statistics and Probability
The distribution of red blood cell counts is different for men and women in a certain population. For both, the distribution is approximately Normal. For men the middle 95% range from 4.34 to 5.95 million cells per microliter, and for women the middle 95% have red blood cell counts between 3.53 and 4.64 million cells per microliter. Complete parts (a) and (b) below
a. What is the mean for the men? Explain your reasoning
b. What is the mean for women? Explain your reasoning
Solution:
Given: The distribution of red blood cell counts is different for men and women in a certain population and the distribution is approximately Normal for both.
Part a) What is the mean for the men? Explain your reasoning
For men the middle 95% range from 4.34 to 5.95 million cells per microliter.
Mean is the center or mid point of confidence interval or center value of middle 95% area is nothing but mean. Since Normal distribution is symmetric about the mean value.
Thus find mid point of given range.
Mid Point = ( Lower Limit + Upper Limit) / 2
Mid Point = ( 4.34 + 5.95) / 2
Mid Point = 10.29
Mid Point = 5.145
Thus mean for the men = 5.145 million cells per microliter.
Part b) What is the mean for women? Explain your reasoning
For women the middle 95% have red blood cell counts between 3.53 and 4.64 million cells per microliter.
Thus find mid point of range 3.53 to 4.64
Mid Point = ( Lower Limit + Upper Limit) / 2
Mid Point = ( 3.53 + 4.64 ) / 2
Mid Point = 8.17 / 2
Mid Point = 4.085 million cells per microliter.
Thus mean for the women = 4.085 million cells per microliter.