Question

The ratio of incomes of two persons is 11 : 7 and the ratio of their expenditures is 9:5 . If each of them manages to save Rs. 400 per month, find their monthly incomes.

Answer 1

let the income of first person be 11x

and his expenditure be 9x

let the income of second person be 7x

and his expenditure be 5x

according to the question

11x-9x=400

x=200

Or

7x-5x=400

x=200

so their income is

First person=2200

second person=1400

Answer 2

Step-by-step explanation:

let incomes be 11x and 7x

and expenditure be 9y and 5y

atq,

11x-9y=400

7x-5y=400

5(11x-9y)=5×400

9(7x-5y)=9×400

55x-45y=2000 ------(i)

63x-45y=3600 ------(ii)

adding both i and ii

118x=5600

x = 47.45

income of person 1= 11× 47.45

= 521.95

income of person 2 = 7×47.45