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?
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 5 of 14.
Chandu said:
7 years ago
Please, anybody, explain it in an easy way.
Vinay said:
7 years ago
The positive numbers from 1 to 14 addition is 105.
The negative numbers i.e. 15, 16, 17, 18, 19, 20 is -105;.
So, the sum of these numbers is 0. And average is zero hence It can only 14 positive numbers.
The negative numbers i.e. 15, 16, 17, 18, 19, 20 is -105;.
So, the sum of these numbers is 0. And average is zero hence It can only 14 positive numbers.
Jeevitha S K said:
7 years ago
If it is asked as "atleast" the answer will be 1 right.
Shreeshail karajol said:
7 years ago
Very simple.
Consider the sum of all 19 number =150.
If 20th is - 150 then,
150+(-150)=0,
Now 0/20=0.
Consider the sum of all 19 number =150.
If 20th is - 150 then,
150+(-150)=0,
Now 0/20=0.
Prudhvi Raju said:
7 years ago
How can you say 20th number is negative?
It may have 10 positive and 10 negative numbers or may be any other combinations.
Please clarify for me.
It may have 10 positive and 10 negative numbers or may be any other combinations.
Please clarify for me.
Ankit Dere said:
7 years ago
It is asked in the question.
Avg of 20 numbers is Zero,
Given avg=0.
Numbers=20.
Explanation:
Avg=sum÷number i.e.
0=sum÷20
Now, cross multiply.
Sum=20x0=0.
This means the sum of 20 numbers is equal to 0.
{1+2+...+20}= is 0.
{1+2+...+19}= Will not be 0.
But the sum of rest 19 number will not be 0 it will be greater than 0(as the 2nd part of the question says how many may be greater than 0?)
Avg of 20 numbers is Zero,
Given avg=0.
Numbers=20.
Explanation:
Avg=sum÷number i.e.
0=sum÷20
Now, cross multiply.
Sum=20x0=0.
This means the sum of 20 numbers is equal to 0.
{1+2+...+20}= is 0.
{1+2+...+19}= Will not be 0.
But the sum of rest 19 number will not be 0 it will be greater than 0(as the 2nd part of the question says how many may be greater than 0?)
(5)
Denis said:
7 years ago
How? Explain me the answer.
Habib said:
7 years ago
Thanks @Praveen.
Saikat said:
7 years ago
Please anyone help I can't understand this.
Subash said:
7 years ago
@Sai.
In the question, they had given AT THE MOST.
So, the maximum value must be the answer.
In the question, they had given AT THE MOST.
So, the maximum value must be the answer.
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