#47 Average Quantitative Aptitude Question

The average of 20 numbers is zero. Of them, at the most, how many may be greater than zero? 

A. 0
B. 1
C. 10
D. 19

Ans: D.Sol.
Average of 20 numbers = 0.
Therefore sum of 20 numbers = (0 × 20 ) = 0.
It is quite possible that 19 of these numbers may be positive and if their sum is a, then 20th number is (- a).