Question

A professor divided the students in her business class into three​ groups: those who have never taken a statistics​ class, those who have taken only one semester of a statistics​ class, and those who have taken two or more semesters of statistics. The professor randomly assigns students to groups of three to work on a project for the course. If​ 10% of the students have never taken a statistics​ class, 35% have taken only one semester of a statistics​ class, and the rest have taken two or more semesters of​ statistics, what is the probability that at least one of the first two groupmates you meet has studied more than one semester of​ statistics?

Answer 1

The probability that at least one of the first two groupmates you meet has studied more than one semester of​ statistics = 0.55 (1 - 0.45).

Explanation:

Probability of those who have never taken a statistics​ class = 0.1 (10%)

Probability of those who have taken only one semester of a statistics​ class = 0.35 (35%)

Therefore, the probability of those who have taken two or more semesters of statistics = 0.55 or 55% (1 - 0.35 - 0.1).