Last year, the number of students in Oscar's class was 20% less than the number of students in Haoxi's class. This year, the enrollment in Oscar's class dropped by 25% and the enrollment in Haoxi's class dropped by 10%. Oscar now has 6 fewer students than Haoxi. How many students were in Haoxi's class last year?
Let x----------> students in Oscar's class last year y----------> students in Haoxi's class last year
we know that Last year the number of students in Oscar's class was 20% less than the number of students in Haoxi's class. so x=0.80y-----> equation 1
this year 0.75x=0.90y-6------> equation 2
using a graph tool see the attached figure
the solution is x=16----> students in Oscar's class last year y=20----> students in Haoxi's class last year this year students in Oscar's class this year------> 0.75*16----> 12 students students in Haoxi's class this year------> 0.90*20----> 18 students
the answer is students in Haoxi's class last year were 20
