Question

In a sample of 150 residents, each person was asked if he or she favored the concept of having a single, countywide police agency. The county is composed of one large city and many suburban townships. The residence (city or outside the city) and the responses of the residents are summarized in the following table. (Enter your probabilities as fractions.)

Residence	Favor	Oppose	Total
In the city	70	40	110
Outside the city	25	15	40
Total	95	55	150

(a)

What is the probability that a randomly selected individual from this group of respondents is in favor of the concept of having a single, countywide police agency?

(b)

Calculate the probability.

The probability that a randomly selected individual from this group of respondents lives in the city is  .

Answer 1

a) Probability that a randomly selected individual from this group of respondents is in favor of the concept of having a single, countywide police agency is computed here as:
= Number of individuals who are in favor / Total residents
= 95/150
= 19/30

Therefore 19/30 is the required probability here.

b) Now the probability that a randomly selected individual from this group of respondents lives in the city is computed here as:
= Number of residents in the city / Total residents
= 110/150
= 11/15

Therefore 11/15 is the required probability here.