Question

A science class has 5 girls and 5 boys in the seventh grade and 5 girls and 3 boys in the eighth grade. The teacher randomly selects a seventh grader and an eighth grader from the class for a competition. What is the probability that the students she selects are both girls? Write your answer as a fraction in simplest form.

Answer 1

Probability that the 7th grader is a boy = number of boys / total kids = 5 / (5+5) = 5/10 or 1/2Probability that the 8th grader is a boy = number of boys / total kids = 3 / (5+3) = 3/8Probability that both are boys is calculated by multiplying both of the answers above: ½ * 3/8 = 3/16 or 0.1875