A survey was conducted from a large group of high school students in an effort to determine what science courses they were currently enrolled in. 68% in Chemistry, 65% in Physics, 47% in Biology.

Question

Assume independence between the science classes that each student is enrolled in.(Round to 3 decimal places, if needed)

a) What is the probability that a randomly selected student is enrolled in chemistry and physics, but not biology?

b) What is the probability that a randomly selected student is enrolled in physics but not chemistry?

c) What is the probability that a randomly selected student is enrolled in chemistry or biology?

Answer 1

a) What is the probability that a randomly selected student is enrolled in chemistry and physics, but not biology?

(0.68)*(0.65)*(0.53) = 0.234

b) What is the probability that a randomly selected student is enrolled in physics but not chemistry?

(0.47) * (0.32) = 0.15

c) What is the probability that a randomly selected student is enrolled in chemistry or biology?

(0.68) + (0.47) - (0.68)*(0.47) = 0.83