The table shows the percentage of students in each of three grade levels who list soccer as their favorite sport. Soccer Sophomores (35%) 50%

Juniors (33%) 45%

Seniors (32%) 30%

Total (100%) (0.5) (0.35) + (0.45) (0.33) + (0.32) (0.3) = 0.4195 or about 42%

Find the probability that the student is a junior, given that soccer is the favorite sport listed.

P (junior | soccer) = ?%

The answer should be roughly 35.4%.

You can obtain this answer by looking at the percentage of each subgrouping. For instance, 33% of the class in juniors and 45% of them list soccer as their favorites. Thus showing that 14.85% of the entire school is made up of juniors that enjoy soccer.

If you do the totaling for all soccer lovers, you get a total of 41.95% of the school. By dividing the two numbers you get the answer above.