Question

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.

Answer 1

Let income of first person `= 9x`
Then, income of second person `= 7x`
Let expenditutres of first person `= 4y`
Then, expenditutres of second person `= 3y`
Now, we are given,
`9x-4y = 2000->(1)`
`7x-3y = 2000->(2)`
From (1) and (2),
`9x-4y = 7x-3y`
`2x = y`
Putting value of `y` in `(1)`
`9x-4(2x) = 2000=>x = 2000` `y = 2000/2 = 1000`
So, income of first person in Rs `= 9x = 18000`
Then, income of second person in Rs `= 7x = 14000`