Question

Student Exercise 2      Studies have concluded that smoking while pregnant can have negative consequences, but could smoking also negatively affect one’s ability to become pregnant? A study2 collected data on 678 women who had gone off birth control with the intention of becoming pregnant.

The results are summarized in the table below.

	Smoker	Non-smoker	Total
Pregnant	38		244
Not pregnant		337	434
Total	135	543

Find the proportions below and express your answers as a decimal rounded to the nearest thousandth.
a. What is the proportion of women who successfully became pregnant who
are smokers?
b. What is the proportion of smokers who are pregnant?
c. What is the proportion of pregnant women who are non-smokers?
d. What is the proportion of women who successfully became pregnant?
e. What is the proportion of non-smoking women who successfully became
pregnant?

Answer 1

	Smokers	Non Smokers	Total
Pregnant	38	(244-38)=206	244
Not pregnant	(434-337)=97	337	434
Total	135	543	678

A) Proportion of women who successfully became pregnant who are smokers = 38/678 = 0.056

B)  Proportion of smokers who are pregnant = 38/135 = 0.281

C) Proportion of pregnant women who are non-smokers = 206/244 = 0.844

D) Proportion of women who successfully became pregnant= 244/678 = 0.359

E) Proportion of non-smoking women who successfully became pregnant= 206/543 = 0.379