Question

The monthly income of a and b are in the in the ratio of 5:4 and their expiditres are in the ratio 7:5 .if each saves rs 9000 per month .find their monthly in comes ? Answer class 10

Answer 1

income a : b = 50 : 40
expen a: b = 7:5
savings a = 50 -7 =43
43 = 9000
1 =9000/43
50 = 50×9000/43 =10465.11 of a

b
40-5 =35
35 =9000
1=9000/35
40 =40×9000/35=10285.71 b

Answer 2

Let income of A & B be 5x,4x.
Expenditure of A &B be 7y,5y.

ATQ
5x - 7y = 9000 (1)
4x - 5y = 9000 (2)
Solve
5x - 7y = 4x -5y
x =2y

put in (1)
10y -7y = 9000
y = 3000
again putting y in (1)

5x = 9000 + 21000
x = 30000/5 = 6000

Therefore monthly income are 5x,4x i.e ₹30000,₹24000