Respuesta :
First, let's find out what percentage of the total group of students lists basketball as their favorite sport:
10th: .41 * .4 = 16.4% of the school are 10th grade ballers
11th: .30 * .35 = 10.5% of the school are 11th grade ballers
12th: .29 * .40 = 11.6% of the school are seniors who drain like Kobe
Total: 38.5% of all students list basketball as their favorite sport.
We divide the portion of 10th grade basketball fans by the total proportion of basketball fans:
16.4% ÷ 38.5% = 42.6%
There is a 42.6% chance that the student is a 10th grader, given that he/she is a basketball fan.
10th: .41 * .4 = 16.4% of the school are 10th grade ballers
11th: .30 * .35 = 10.5% of the school are 11th grade ballers
12th: .29 * .40 = 11.6% of the school are seniors who drain like Kobe
Total: 38.5% of all students list basketball as their favorite sport.
We divide the portion of 10th grade basketball fans by the total proportion of basketball fans:
16.4% ÷ 38.5% = 42.6%
There is a 42.6% chance that the student is a 10th grader, given that he/she is a basketball fan.