1200 students enrolled. 451 students take Calculus, 656 students take Statistics and 313 students take both. What is the probability that a random student takes Calculus or Statistics?

Answer 1

451 students take Calculus, 656 students take Statistics and 313 students take both

If 451 students take calculus, 656 take stats, and 313 take both, the total number of students taking either calculus or stats is 451 + 656 - 313 = 794 students. We are subtracting 313 because when we added 451 and 656, we are actually counting the students who take both twice - so we need to discount them once.

With this, the probability of a random student taking either calculus or statistics would be 794 / 1200 = about 66.2%.