A survey is made in a neighborhood of 80 voters 65 are Democ

A survey is made in a neighborhood of 80 voters. 65 are Democrats and 15 are Republicans. Of the Democrats, 35 are women, while 5 of the Republicans are women. If one subject from the group is randomly selected, find the probability the individual is a Democrat or a Republican.

Solution

P(D) = 65/80 = 0.8125
P(R) = 15/ 80 = 0.1875

P(Democrate Women) = 35 / 80 = 0.4375
P(Republican Women) = 5/80 = 0.0625
P( Male Republican) = 10 / 80 = 1/8 = 0.125

P( Democrate or Republican) = P(D) + P(R) - P(D n R) = 0.8125+0.1875 = 1.00