Pollsters are concerned about declining levels of cooperation among persons contacted in surveys. a pollster contacts 90 people in the 18-21 age bracket and finds that 76 of them respond and 14 refuse to respond. when 297 people in the 22-29 age bracket are contacted, 262 respond and 35 refuse to respond. assume that 1 of the 387 people is randomly selected. find the probability of getting someone in the 18-21 age bracket or someone who agreed to respond. report the answer as a percent rounded to one decimal place accuracy. you need not enter the "%" symbol. prob = 23.3 incorrect%

Answer: 91.0%

To find this, create a two way table.
On the top row, put the 18-21 group with the 76 responding then 14 not responding.
On the second row, put the 22-29 group with 262 responding then 35 not responding.

We are looking for people in the 18-21 group, those are the numbers 76 and 14. However, we must also include those in the older group that responded, 262.

So our fraction becomes (76 + 14 + 262 ) / 387 or 91.0%

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