# Find the Difference in Their Monthly Incomes :

A and B have their monthly incomes in the ratio 8:5, while their monthly expenditures are in the ratio 5:3, If they have saved ₹ 12,000 and ₹ 10,000 monthly respectively, then the difference in their monthly incomes is

1. ₹ 52,000
2. ₹ 44,000
3. ₹ 46,000
4. ₹ 42,000
Anurag Mishra Professor Asked on 26th October 2015 in

Answer is (4): Rs. 42,000

Explanation:-
The ratio of the income of A  and B = 8: 5
Let the income of A be = 8 X and the income of B = 5 X

The ratio of their expenditures = 5: 3
Let the expenditure of A = 5 Y  & the expenditure of B = 3 Y

Then, 8 X – 5 Y = 12, 000 ………………………………. (1)
5 X – 3 Y = 10, 000     ……………………………………….(2)
In equation (1) multiply by 3 & in equation (2) multiply by 5
Then, 24 X – 15 Y = 36, 000        ………………(3)
25 X – 15 Y  = 50, 000                           …………(4)
equation (3) is subtracted from (4),
Then, 25 X – 24 X – 15 Y + 15 Y = 50, 000 – 36, 000
X = 14, 000

Then, the monthly in come of A =8 X = 8 x 14, 000
= 1, 12, 000
And the monthly income of B = 5 X = 5 x 14, 000
= 70, 000

Then, the difference between their monthly income = 1, 12, 000 – 70, 000
= Rs. 42, 000

Hence, the answer is (4) Rs. 42, 000

Monis Rasool Professor Answered on 28th October 2015.