Question

25. There are two classrooms A and B. If 10 students are sent from A to B,
the number of students in each room becomes the same. If 20 students
are sent from B to A, the number of students in A becomes double the
number of students in B. Find the number of students in each room.
the combinin​

Answer 1

Let the number of students in classroom A be x Let the number of students in classroom B be y. If 10 students are transferred from A to B then we have: x – 10 = y + 10 ⇒x – y = 20 …..i If 20 students are transferred from B to A then we have: 2y – 20 = x + 20 ⇒2y – 40 = x + 20 ⇒ -x + 2y = 60 …..iiOn adding i and ii we get: y = 20 + 60 = 80 On substituting y = 80 in i we get: x – 80 = 20 ⇒x = 20 + 80 = 100 Hence the number of students in classroom A is 100 and the number of students in classroom B is 80.