Question

I like to help in this problem: in the course of Juan 2/9 of the students are children of 13 years, 1/4 have 14 years and the rest 15 years What kind of students do they have?

Answer 1

rest are 19/36

it is 1 -(1/4) - (2/9)
= 1-9/36 - 8/36
= (36-9-8)/36
= 19/36.