Five hundred high school students were surveyed and asked their favorite core subject. The following table displays the results.

Question

English SocialStudies Math Science Total

9th Grade 20 30 10 20 80

10th Grade 25 40 30 30 125

11th Grade 15 20 40 25 100

12th Grade 15 35 70 75 195

Total 75 125 150 150 500

What is the probability that a randomly selected person will prefer math, given the student is in the 11th grade?

Please explain the answer and show the math used to arrive at the answer.

Answer 1

There are 100 students in 11th grade and 40 selected math therefore the probability is 40/100 or 2/5 or 40%.