Question

12. Pollsters are concerned about declining levels of cooperation among persons contacted in surveys. A pollster contacts 92 people in the​ 18-21 age bracket and finds that 47 of them respond and 45 refuse to respond. When 261 people in the​ 22-29 age bracket are​ contacted, 213 respond and 48 refuse to respond. Suppose that one of the 353 people is randomly selected. Find the probability of getting someone in the 18 dash 21 age bracket or someone who responded.

​P(person is in the 18-21 age bracket or responded​)=_____

​(Do not round until the final answer. Then round to three decimal places as​ needed.)

13.The table below summarizes results from a study of people who refused to answer survey questions. A market researcher is interested in​responses, especially from those between the ages of 22 and 39. Find the probability that a selected subject responds or is between the ages of 22 and 39.

_   18-21   22-29   30-39   40-49   50-59   60_and_over
Responded   72   254   244   135   137   201
Refused   12   21   34   27   36   58

The probability that the subject responded or is between the ages of 22 and 39 is_____

​(Round to three decimal places as​ needed.)

14. The table below summarizes results from a study of people who refused to answer survey questions. A market researcher is not interested in refusals or subjects below 22 years of age or over 59. Find the probability that the selected person refused to answer or is below 22 or is older than 59.

Age   Responded   Refused
18-21   72   10
22-29   254   19
30-39   244   32
40-49   135   25
50-59   137   34
60 and over   201   56

The probability that a randomly selected person refused to answer the survey question or is below 22 or is older than 59 is_____

​(Do not round until the final answer. Then round to three decimal places as​ needed.)

Answer 1

Question 12:

We are given the below information in question 12:

	Responded	Not responded	Total
18-21	47	45	92
22-29	213	48	261
Total	260	93	353

P(person is in the 18-21 age bracket or responded ) is given below:

$\boldsymbol{\frac{92}{353}+\frac{260}{353}-\frac{47}{353}=\frac{305}{353}=0.864}$

P(person is in the 18-21 age bracket or responded ) = 0.864

Question 13:

Answer:

We are given the below information:

Age	Responded	Refused	Total
18-21	72	12	84
22-29	254	21	275
30-39	244	34	278
40-49	135	27	162
50-59	137	36	173
60 and over	201	58	259
Total	1043	188	1231

The probability that the subject responded or is between the ages of 22 and 39 is

$\boldsymbol{\frac{1043}{1231}+\frac{553}{1231}-\frac{498}{1231}=\frac{1098}{1231}=0.892}$

Therefore, the probability that the subject responded or is between the ages of 22 and 39 is $\boldsymbol{0.892}$

Question 14:

Answer:

We are given the below information:

Age	Responded	Refused	Total
18-21	72	10	82
22-29	254	19	273
30-39	244	32	276
40-49	135	25	160
50-59	137	34	171
60 and over	201	56	257
Total	1043	176	1219

The probability that a randomly selected person refused to answer the survey question or is below 22 or is older than 59 is given below:

$\boldsymbol{\frac{176}{1219}+\frac{72}{1219}+\frac{201}{1219}=\frac{449}{1219}=0.368}$

Therefore, the probability that a randomly selected person refused to answer the survey question or is below 22 or is older than 59 is $\boldsymbol{0.368}$