Question

The average monthly income of three persons is rs. 3,600. If the income of the first is 1/5 of the combined income of the other two then his monthly income is

Answer 1

The value of 0-2 + 0-3 + 0-32 is— (A) 0-87 (B) 0-77 (C) 0-82 (D) 0-86 25. ... If sum of their income is Rs. 7800, then B's income is — (A) Rs. 3600

Answer 2

Given:

Number of people = 3

Total amount of income = Rs. 3,600

Income of the first = 1/5 of the combined of the other two.

To find :

Income of the first

Solution:

Let income of the first be A

let income of the second be B

let Income of the third be C

Income = 3600 = A+B+C

$A+B+C = 3600$

let this be equation 1

Income for the first = 1/5(B+C)

$A= \frac{1}{5} (B+C)$

$A = \frac{(B+C)}{5}$

$5A = (B+C)$

let this be equation 2

solving equation 1 and 2

$A+B+C = 3600$

$\frac{(B+C)}{5} +B+C = 3600$

$\frac{(B+C) + 5B+5C}{5} = 3600$

$B+C + 5B+5C = 3600 \times 5$

$6B+6C = 3600 \times 5$

$\frac{6(B+C)}{5} = 3600$

$6(B+C) = 3600 \times 5$

$6A = 3600$

$A = \frac{3600}{6}$

$A = 600$

Verification.

$A+B+C = 3600$

$600+B+C = 3600$

$B+C = 3600 - 600$

$B+C = 3000$

using equation 2

$5A = 3000$

$A = \frac{3000}{5}$

$A = 600$

Therefore the value of A = 600.

The income of the first is Rs. 600