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Example 3.16 Cell Phone Features (Multiplication Rule) When the conditional probability of text messaging, given photo capability, 0.65 PAB) 0.8125 0.80 is multiplied by the probability of photo capability, we have the joint probability of both messaging and photo capability: PLAN B) = (0.8125 (0.80) = 0.65 In the following example we see an interesting application of the multiplication rule of probabilities. We also tie together some ideas introduced previously Example 3.17 Sensitive Questions (Multiplication Rule) Suppose that a survey was carried out in New York, and each respondent was faced with the following two questions: a. Is the last digit of your Social Security number odd? b. Have you ever lied on an employment application? The second question is, of course, quite sensitive, and for various reasons we might expect that a number of people would not answer the question honestly, especially if 975 . flip a coin and then to answer question (a) if the result was "head" and answer (b) oth- erwise. A yes response was given by 37% of all respondents. What is the probability that a respondent who was answering the sensitive question, (b), replied yes