• We are told that there were 3/8 in the begining , where 3 is the number of advaced maths and 8 is the number of regular maths .
,
• 4 /7 were the final results . meaning 4 advanced and 7 regular maths
,
• 4/7 : 92/x ( where x is final advanced, and x is the regular maths )
so, 3+8 = 11 and 4+7 = 11
if 92 students are equal to 4 in the final ratio;
92 / 4 = 23 in the ratio of 1
therefore :
if 4 : 92
then 7 : 23
7 x 23 = 161 students in regular maths
161 + 92 = 253 students in total
(extra notes :if you want to find the original class numbers
253 /11 = 23
23 X 3 = 69
23 X8 = 184
this means that there were 69 advanced and 184 regular students)