A principal simulated a student raffle using 500 trials and recorded the grade level of the winner each time. The results are shown in the table

Question

Based on the data from the simulation, what is the probability that the winner will be in Grade 11?

Students     Grade 9    Grade 10   Grade 11   Grade 12       

Frequency  152               130             80              98

Answer 1

The sum of these counts is 460, not 500 as would be expected, so we conclude that 40 students are outside the listed grades. Assuming that to be the case, the number of grade 11 winners is 80/500 of the total number of students, that is, 0.16 or 16%. This is the probability that the winner would be a grade 11 student.