Question

The ratio of incomes of A and B is 2 : 1 and the ratio of their expenditure is 5 : 2. If each saves 300 per month, the income of B is
(1) 700
(2) 1200
(3) 900
(4) ? 1800​

Answer 1

Step-by-step explanation:

Let income of A and B be 3x and 2x respectively. Also, their expenditure is 5y and 3y.

⇒  Now, according to question,

⇒  3x−5y=1000              ---- ( 1 )

⇒  2x−3y=1000          ----- ( 2 )

⇒  Now, multiplying  equation ( 1 ) by 3 and ( 2) by 5.

⇒  9x−15y=3000               ---- ( 3 )

⇒  10x−15y=5000           ----- ( 4 )

⇒  x=2000                [Subtraction equation ( 3 ) from equation ( 4 ) ]

⇒ Then, income of A = 3x=Rs.(3×2000)=Rs,.6000.

Answer 2

Answer:

(3) 900

Step-by-step explanation:

income ratio- 2:1 -> 6 : 3, (multiply by 3)

1| |1

expenditure ratio - 5 : 2

they both saves- 1 unit each.

according to the question they saves-300

then, 1unit= 300

according to the income ratio B saves 3 unit.

then, the income of B is (3*300) = 900