Question

The monthly incomes of two persons are in the ratio of 4:5 and their monthly expenditures are in the ratio of 7:9. If each saves Rs. 50 a month, then what are their monthly incomes?

• A. Rs. 100, Rs. 125
• B. Rs. 200, Rs. 250
• C. Rs. 300, Rs. 375
• D. Rs. 400, Rs. 500

Answer 1

The Correct Option is D

The correct option is (D): Rs. 400, Rs. 500
Explanation:

Assume the monthly incomes are Rs. \(4x\) and \(5x\) for two individuals, and their monthly expenditures are Rs. \(7y\) and \(9y\) respectively.
From the question, we have these equations:
\(4x−7y=50 \)
\(5x−9y=50\)

By solving these equations, we get that \(y=50\) and \(x=100\). Therefore, the monthly incomes are Rs. 400 and Rs. 500 respectively.