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**somestudent2** A population of voters contains 40% Republicans and 60% Democrats. It is reported that 30% of the Republicans and 70% of the Democrats favor an election issue. A person chosen at random from this population is found to favor the issue in question. Find the conditional probability that this person is a Democrat.

Here is what I did.

Let P(r) person chosen is a republicant = 0.4

Let P(d) person chosen is a democrat = 0.6

P(a|r) person supports issue given he\she is republicant = 0.3

P(a|d) person supports issue given he\she is democrat = 0.7