(1) Let monthly incomes of A, B andC be x, y and z, respectively. So, x + y = 2 × 15050 = Rs. 30100 y + z = 2 × 15350 = Rs. 30700 z + x = 2 × 15200 = Rs. 30400 Adding all three we get, x + y + z = Rs. 45600 So, (x + y + z) – (y + z) = 45600 –30700, x = Rs. 14900