Suppose that 55 of all adults regularly consume coffee 45 r

Suppose that 55 % of all adults regularly consume coffee, 45% reguarly consume, soda, and 70% regularly consume at least one of these two products. What is the probability that a randomly selected adult regularly consumes both coffee and soda? What is the probability that a randomly selected adult doesnt regularly consume either of these two products?

Solution

a) it is given that 55% consume coffee and 70% consume atleast one of both and only 45% consume soda

which means to get probability of those who consume both will be = 70-55 = 15% = 0.15

b) it is given 70% consume atleast one

therefore it means 100 -70 = 30% doesnt consume any

hence probability = 30% = 0.30