The average monthly income of A and B is Rs. 5050. The average monthly income of B and C is Rs. 6250 and the average monthly income of A and C is Rs. 5200. What is the monthly income of A?  Choose the correct answer.
A) 1000  B) 1500  C) 2000  D) 3000  E) 4000
Let monthly income of A = a   monthly income of B = b   monthly income of C = c   a + b = 2 × 5050 .... (Equation 1)   b + c = 2 × 6250 .... (Equation 2)   a + c = 2 × 5200 .... (4000quation 3)   (4000quation 1) + (4000quation 3) - (4000quation 2)   =&gt; a + b + a + c - (b + c) = (2 × 5050) + (2 × 5200) - (2 × 6250)   =&gt; 2a = 2(5050 + 5200 - 6250)   =&gt; a = 4000   i.e., Monthly income of A = 4000   Answer is 4000.
<result>E</result>
The average monthly income of A and B is Rs. 5050. The average monthly income of B and C is Rs. 6250 and the average monthly income of A and C is Rs. 5200. What is the monthly income of A?