Question

In a survey of 2000 adults 50 years and older of whom 80% were retired and 20% were pre-retired, the following question was asked: Do you expect your income needs to vary from year to year in retirement? Of those who were retired, 25% answered no, and 75% answered yes. Of those who were pre-retired, 26% answered no, and 74% answered yes. If a respondent in the survey was selected at random and had answered yes to the question, what is the probability that he or she was retired? (Round your answer to three decimal places).

Answer 1

Sounds like a conditional probability situation. Making a two-way table will probably help.