Suppose the contact rate for a phone survey is 78% and that 22% of people will participate in that survey. Assume that agreeing or not agreeing to participate is independent of whether the house is contacted.
a) What is the probability that the next house will be contacted and refuse to cooperate?

b) What is the probability of failing to contact a house, or making contact and not getting them to agree to the interview?

Question

Suppose the contact rate for a phone survey is 78% and that 22% of people will participate in that survey. Assume that agreeing or not agreeing to participate is independent of whether the house is contacted. 
a) What is the probability that the next house will be contacted and refuse to cooperate?

b) What is the probability of failing to contact a house, or making contact and not getting them to agree to the interview?

anonymous · Answer

I got 60.84 for A...

anonymous · Answer

If no one else helps you, khanacademy.com may be a useful source. How to do this has slipped my mind. :/

phi · Answer

a) prob of contacting is 0.78 * prob refuse (1- 0.22)= 0.6084 or 60.84%
looks good
for (b), draw a probability tree
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