This is the Important question based on Linear Equations in two Variables Chapter of R.S Aggarwal book for ICSE & CBSE Board.

Question Number 25 Exercise 3E of RS Aggarwal Solution

Here are two classrooms A and B is given.

If n number of students are sent from A to B and B to a respectively the number of students in each room becomes the same and the number of students in A become double the number of student in B.

You have to find the number of Students in each room.

Deepak BoraNewbie

# 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.

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Two number of classrooms are 2. They are A and B.

Let the number of students in A be x and number of students in B be y.

(i)

10 students are send from A to B.

⇒ x – 10 = y + 10

⇒ x – y = 20

(ii)

20 students are sent from B to A, the number of students become double.

⇒ x + 20 = 2(y – 20)

⇒ x + 20 = 2y – 40

⇒ x – 2y = -60

On solving (i) & (ii), we get

⇒ x – y = 20

⇒ x – 2y = -60

———————–

y = 80

Substitute y = 80 in (i), we get

⇒ x – y = 20

⇒ x – 80 = 20

⇒ x = 100.

Therefore:

Number of students in classroom A = 100.

Number of students in classroom B = 80.