Q) The monthly income of Aryan and Babban are in the ratio 3:4 and their monthly expenditures are in ratio 5:7. If each saves ₹ 15,000 per month, find their monthly incomes.

Q31 A – Sample Question Paper – Set 1 – Maths Standard – CBSE 2026

Ans: 

Let the income of Aryan and Babban be 3 X and 4 X

Since Saving = Income – Expenditure

or we can say, Expenditure = Income – Savings

Given that saving of both person is 15,000

hence, expenditure of Aryan = 3 X – 15,000

and expenditure of Babban = 4 X – 15,000

Since the ratio expenditures is given as 5 : 7

Therefore, (3 X – 15000) / (4X – 15000) = 5 / 7

∴ 7 (3 X – 15000) = 5 (4 X – 15000)

∴ 21 X – 7 x 15000 = 20 X – 5 x 15000

∴ 21 x – 20 x = 7 x 15000 – 5 x 15000

∴  X = 15000 ( 7 – 5)

∴  X = 15000 x 2

∴  X = 30000

Therefore the income of Aryan = 3 X = 3 x 30000 = 90,000

and income of Babban = 4 X = 4 x 30000 = 120,000

Therefore the incomes of Aryan and Babban are 90,000 and 120,000 respectively.

Please do press “Heart” button if you liked the solution.