The monthly incomes of two friends Vipul and Vijay, are in the ratio 5 : 7 respectively and each of them saves ₹81000 every month. If the ratio of their monthly expenditure is 2 : 4, find the monthly income of Vipul(in ₹).

Given:

Ratio of monthly incomes of Vipul and Vijay = 5 : 7

Monthly saving of each = ₹81000

Ratio of their monthly expenditure = 2 : 4

Formula Used:

Income = Expenditure + Saving

Calculation:

Let the monthly income of Vipul be 5x and the monthly income of Vijay be 7x.

Expenditure of Vipul = Income of Vipul - Saving of Vipul = 5x - 81000

Expenditure of Vijay = Income of Vijay - Saving of Vijay = 7x - 81000

Ratio of their monthly expenditure = (5x - 81000) : (7x - 81000) = 2 : 4

⇒ (5x - 81000) / (7x - 81000) = 2 / 4

⇒ (5x - 81000) / (7x - 81000) = 1 / 2

⇒ 2 × (5x - 81000) = 1 × (7x - 81000)

⇒ 10x - 162000 = 7x - 81000

⇒ 10x - 7x = 162000 - 81000

⇒ 3x = 81000

⇒ x = 81000 / 3

⇒ x = 27000

Monthly income of Vipul = 5x = 5 × 27000 = ₹135000

The monthly income of Vipul is ₹135000.