The correct question is:
A study of consumer smoking habits includes 167 people in the 18-22 age bracket (59 of whom smoke), 148 people in the 23-30 age bracket (31 of whom smoke), and 85 people in the 31-40 age bracket (23 of whom smoke). If one person is randomly selected from this sample, find the probability of getting someone who is age 23-30 or smokes
Answer:
The probability of getting someone who is age 23-30 or smokes = 0.575
Explanation:
We are given;
Number consumers of age 18 - 22 = 167
Number of consumers of ages 22 - 30 = 148
Number of consumers of ages 31 - 40 = 85
Thus,total number of consumers in the survey = 167 + 148 + 85 = 400
We are also given;
Number consumers of age 18 - 22 who smoke = 59
Number of consumers of ages 22 - 30 who smoke = 31
Number of consumers of ages 31 - 40 who smoke = 23
Total number of people who smoke = 59 + 31 + 23 = 113
Let event A = someone of age 23-30 and event B = someone who smokes. Thus;
P(A) = 148/400
P(B) = 113/400
P(A & B) = 31/400
Now, from addition rule in sets which is given by;
P(A or B) = P (A) + P (B) – P (A and B)
We can now solve the question.
Thus;
P(A or B) = (148/400) + (113/400) - (31/400)
P(A or B) = 230/400 = 0.575