Question

Pollsters are concerned about declining levels of cooperation among persons contacted in surveys. A pollster contacts 95 people in the 18-21 age bracket and finds that 81 of them respond and 14 refuse to respond. When 247 people in the 22-29 age bracket are contacted, 215 respond and 32 refuse to respond. Assume that 1 of the 342 people is randomly selected. Find the probability of getting someone in the 22-29 age bracket or someone who refused to respond.

Answer 1

Answer: Our required probability is 0.097.

Step-by-step explanation:

Since we have given that

Age group                  respond                refused to respond              total

18-21                                81                                      14                             95

22-29                              215                                    32                           247

Total                               296                                    46                           342

So, probability of getting someone in the 22-29 age bracket or some one who refused to respond.

So, it becomes P(22-29 age group) × P(who refused to respond)

$\dfrac{247}{342}\times \dfrac{46}{342}\\\\=\dfrac{247\times 46}{342\times 342}\\\\=\dfrac{11362}{116964}\\\\=0.097$

Hence, our required probability is 0.097.