Question

The ratio of incomes of two persons is 9:7 . The ratio of their expenses is 4:3. Every person saves rupees 200,find the income of each.

Answer 1

Answer: 1800 and 1400

Step-by-step explanation:

The ratio of incomes of two persons is 9:7

∴ Let their incomes be 9x and 7x

The ratio of their expenses is 4:3

∴ Let their expenses be 4y and 3y

Each person saves 200

savings = income - expenses

9x - 4y = 200     ..... 1

7x - 3y = 200     ..... 2

To use the method of elimination

equation 1 can be rewritten as 27x - 12y = 600 by multiplying all the terms by 3

equation 2 can be rewritten as 28x - 12y = 800 by multiplying all the terms by 4

Subtracting equation 1 from 2

(28x - 12y) - (27x - 12y) = 800 - 600

28x - 12y - 27x + 12y = 200

x = 200

Hence the income of the two persons = 9x = 9 X 200 = 1800 and 7x = 7 X 200 = 1400