The monthly salaries of A and B are the same. A, B and C donate 10%, 8% and 9% respectively, of their monthly salaries to a charitable trust. The difference between the donations of A and B is Rs. 400. The total donation by A and B is Rs. 900 more than that of C. What is the monthly salary of C?

Solution (By Examveda Team)

Let the salary of A and B be 100x each and C be 100y
Money donate by A = 100x × $$\frac{{10}}{{100}}$$ = 10x
Money donate by B = 100x × $$\frac{8}{{100}}$$ = 8x
Money donate by C = 100y × $$\frac{9}{{100}}$$ = 9y
According to the question
⇒ 10x - 8x = 400
⇒ 2x = 400
⇒ x = 200
Total donation of A and B = 10x + 8x = 18x
⇒ 18 × 200 = 3600
The total donation by A and B is Rs. 900 more than that of C
⇒ 3600 - 9y = 900
⇒ 9y = 2700
⇒ y = 300
Monthly salary of C = 100y = 100 × 300 = 30000
∴ Monthly salary of C is Rs. 30000