James surveyed people at school and asked whether they
bring their lunch to school or buy their lunch at school more
often. the results are shown below
the events "male" and "buys lunch" are not independent
because
bring lunch: 46 males, 254 females
buy lunch: 176 males, 264 females
pbuys lunch | male) = p(male) = 0.4
p(male | buys lunch) = p(male) = 0.3.
p(buys lunch | male) = 0.3 and p(male) = 0.4
p(male | buys lunch) = 0.4 and p(male) = 0.3.