Example A:
It is suspected that oral contraceptives reduce the hemoglobin levels of their users.
Assume that the hemoglobin levels for the population of women who reported that
they were taking oral contraceptives were Normally distributed with mean 14.48,
and standard deviation of 2.96.
1. Find the probability that a randomly selected woman from the above popula-
tion has a hemoglobin level is less than 13. 2. Without assuming normality of the population distribution, find the probabil-
ity that the hemoglobin levels of a random sample of 36 women who reported that they were taking oral contraceptives will produce a mean less than 13. 3. Find the probability that at most 2 out of 5 women taking oral contraceptives will have hemoglobin levels less than 13. r &+
Solution:
&
f
2
R&of13bi ,&& Di. LR,~ C W:
ym ~ ( 1 * . 9 6 , 2 . 9 6 3
y =
1*
t
(
1-96 ) = P(~<---59
) p ( z 1 3~-l+Y8- p ( 2 7*50) = ,3065 9a-
bhsqj,
ETa, c i r
Ge8
0V-J -
,%-(4.yk7a-96Y
- . Y(/Y~P,=~)
2.a
x
w h&
6-
X
= 2.766
. wj-