Three positive number are given. If the average of any two of them is added to the third number, the sums obtained are 172, 216 and 180. What is the average of the given three numbers?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 
Let the three numbers be x, y and z
According to question,
(x + y)/2 + z = 172 or x + y + 2z = 344 ...(1)
(y + z)/2 + x = 216 or y + z + 2x = 432 ...(2)
(z + x)/2 + y = 180 or z + x + 2y = 360 .....(3)
By adding (1), (2) and (3) we get,
4(x + y + z) = 1136 or (x + y + z) = 284
Average = 284/3 or