Subject: General Aptitude · Chapter: Average · Exam: 2002 · Marks: · Difficulty:
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
Answer
Answer (as printed): D
Explanation
Average of 20 numbers $=0$. ∴ Sum of 20 numbers $=(0 \times 20)=0$. It is quite possible that 19 of these numbers may be positive and if their sum is $a$, then 20 th number is $(-a)$.
Explanation as extracted from the printed page; notation may be imperfect.