Question

A survey of 200 people was conducted to see if they smoke. The results are shown below:

	Male	Female	Total
Smokes	87	74	161
Doesn't smoke	22	17	39
Total	109	91	200

If a person is selected at random, what is the probability that the person is a male or is a smoker?

A.

1.785

B.

correct answer is not given

C.

0.915

D.

0.423

If a person is selected at random, what is the probability that the person is a male given that the person was a smoker?

A.

0.435

B.

0.798

C.

0.540

D.

correct answer is not given

Answer 1

If a person is selected at random, then the probability that the person is a male or is a smoker

$=\frac{109}{200}+\frac{161}{200}-\frac{87}{200}$

=0.915

Option C) is correct.

If a person is selected at random, then the probability that the person is a male given that the person was a smoker

$=\frac{87}{161}$

=0.540

Option C) is correct.