Question

A math class has 3 girls and 7 boys in the 7th grade and 5 girls and 5 boys in the 8th grade the teacher randomly selects a seventh grader and an 8th grader from the class for a completion what is the probability that the students she selects are both girls

Write your answer as a fraction

Answer 1

In the 7th and 8th grade combined, there 3+5 girls = 8 girls, and 7+5 boys = 12 boys. If there are only boys and girls, then there are 12+8=20 students in all.

The fraction of girls out of the total is P = 8/20 = 2/5.