Aptitude - Average - Discussion

Discussion Forum : Average - General Questions (Q.No. 4)
4.
The average of 20 numbers is zero. Of them, at the most, how many may be greater than zero?
0
1
10
19
Answer: Option
Explanation:

Average of 20 numbers = 0.

Sum of 20 numbers (0 x 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).

Discussion:
135 comments Page 13 of 14.

Akshay said:   7 years ago
Here,

If we take 20 numbers in this way.

-10,-9,-8,-7,-6,-5,-4,-3,-2,-1,1,2,3,4,5,6,7,8,9,10.

Sum = 0,
Avg = Sum/no however Avg= 0/20,
Answer should be option C.

Yama said:   6 years ago
Thanks @Harika.

Seethu said:   6 years ago
@Akshay.

It is also a possible case but in the question it is mentioned as "atmost positive numbers".

Suppose if we consider.

1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19.

As 19 positive numbers and the 20th number as -189.

Then we will get maximum positive numbers.

Nagesh said:   6 years ago
When the sum of +ve no.'s = sum of -ve no.'s.

Then Average is Zero.
Sum of Maximum possible.

+ve/-ve numbers = -ve/+ve number.
Hence avg is zero.
And the answer is 19.

Afroz said:   6 years ago
If the question includes "at least ".

Then the answer is 1.

Vijay said:   6 years ago
If you consider 20 numbers for example like.
-10,-9,.....,-1,+1,+2,.....+10.

Then the no of numbers greater than 0 is 10.

Rafi said:   6 years ago
The average of two numbers A and B is 20, that of B and C is 19 and of C and A it is 21. What is the value of A?

Shanthini said:   5 years ago
@Tarun.

Good explanation. Thank You.

SOUMYADEEP said:   5 years ago
Here, it is asked that, how many numbers may be greater than 0 and not will be greater than 0! please explain the difference?

Parikshit said:   5 years ago
The answer could be 10.


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