In 2022, ratio of incomes of 'C' and 'D' was 9:7 respectively, while the ratio of their expenses was 7:4 respectively, and savings of 'C' is Rs. 9,000 more than that of 'D'. In 2023, expenditure of 'C' increases by 25% while his income remains the same. If the savings of 'C' in 2023 was Rs. 2,000 more than that of 'D' in 2022, then find the expenditure of 'D' in 2022.

Let the incomes of 'C' and 'D', in 2022, be Rs. '9x' and Rs. '7x', respectively. Let the expenses of 'C' and 'D', in 2022, be Rs. '7y' and Rs. '4y', respectively. Savings of 'C' in 2022 = Rs. (9x – 7y) Savings of 'D' in 2022 = Rs. (7x – 4y) ATQ: (9x – 7y) – (7x – 4y) = 9000 Or, 2x – 3y = 9000 ……. (I) Expenses of 'C' in 2023 = 7y × 125% = Rs. '8.75y' So, savings of 'C' in 2023 = Rs. (9x – 8.75y) ATQ: (9x – 8.75y) – (7x – 4y) = 2000 Or, 2x – 4.75y = 2000 …… (II) On subtracting equation (II) from equation (I), we have; 1.75y = 7000 So, y = 4000 So, expenditure of 'D' in 2022 = 4 × 4000 = Rs. 16,000