# The ratio of incomes of two persons is 9 : 7 and the ratio of their expenditures is 4 : 3. If each of them manages to save Rs 2000 per month, find their monthly incomes

**Solution:**

Given the ratio of the income is 9: 7 and the ratio of their expenditure is 4: 3.

Let the incomes of the persons be x and their expenditures be y.

⇒ The income of the people is 9x and 7x.

⇒ The expenditure of the persons is 4y and 3y.

If both of them manage to save Rs 2000 per month.

9x - 4y = 2000 be equation 1.

7x - 3y = 2000 be equation 2.

Step 1: Multiply equation 1 by 3 and equation 2 by 4.

27x - 12y = 6000 be equation 3

28x - 12y = 8000 be equation 4

Step 2: Subtract equation 3 from equation 4.

(28x - 12y = 8000) - (27x - 12y = 6000)

x = 2000

The monthly income of one person is 9x = 9 × 2000 = Rs 18,000 and that of another person is 7x = 7 × 2000 = Rs 14,000.

ā Check: NCERT Solutions for Class 10 Maths Chapter 3

## The ratio of incomes of two persons is 9 : 7 and the ratio of their expenditures is 4 : 3. If each of them manages to save Rs 2000 per month, find their monthly incomes

**Summary:**

The monthly incomes of the two persons, if the ratio of their incomes is 9 : 7 and the ratio of their expenditures is 4 : 3 is Rs 18,000 and Rs 14,000 respectively.

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