The monthly incomes of Arjun, Rohan, and Sameer are in the ratio of 7:9:8, while their monthly expenditures are in the ratio of 3:4:5. Arjun earns Rs. 21,000 per month and saves Rs. 9,000 from his income. Based on this information, determine Sameer’s monthly savings.

ATQ;
Let monthly income of ‘Arjun’, ‘Rohan’ and ‘Sameer’ be Rs. ‘7x’, Rs. ‘9x’ and Rs. ‘8x’, respectively.
ATQ;
‘7x’ = 21000
Or, x = 3000
So, monthly income of ‘Sameer’ = ‘8x = 8 × 3000 = Rs. 24,000
Let monthly expenditures of ‘Arjun’, ‘Rohan’ and ‘Sameer’ be Rs. ‘3y’, Rs. ‘4y’ and Rs. ‘5y’, respectively.
Monthly savings of ‘Arjun’ = Rs. 9,000
ATQ,
(21000 – 3y) = 9000
Or, 3y = 12000
So, y = 4000
So, monthly expenditure of ‘Sameer’ = 5y = 5 × 4000 = Rs. 20,000
Therefore, monthly saving of ‘Sameer’ = (24000 – 20000) = Rs. 4,000