I am really confused with this problem. The question is :
If the sum of n consecutives is o, which is the following must be true.
1. n = even
2. n = odd
3. the average of n integer is 0.
The answer of 2 & 3 must be true, and I don't see why n= odd
In order for the average = 0
the sum of number has to be 0.
sum of numbers/number of numbers = average
is the sum = 0, then the average is 0
in order for that to happen, we need equal number of same number with opposite signs to cancel each other, for example(-3)+(-2)+(-1)+(0)+(1)+(2)+(3), i can also have (-4)+(-2)+0+(2)+(4)
then the sum being odd number or even number would be irrelevent, right?
Then, why the official answer should be 2 &3?
Thanks!!!
problem 201
This topic has expert replies
I'll use a piece from ur post only,
does the part in bold represent consecutive integers??in order for that to happen, we need equal number of same number with opposite signs to cancel each other, for example(-3)+(-2)+(-1)+(0)+(1)+(2)+(3), i can also have (-4)+(-2)+0+(2)+(4)
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You just bug a little
As you explained if you want the consecutive sum to be equal to 0 you can have (-3)+(-2)+(-1)+(0)+(1)+(2)+(3), i can also have (-4)+(-2)+0+(2)+(4)
They do not ask you if the numbers are odd or even, they ask you if "n" is odd or even. In your examples n=7 and n=5
As you explained if you want the consecutive sum to be equal to 0 you can have (-3)+(-2)+(-1)+(0)+(1)+(2)+(3), i can also have (-4)+(-2)+0+(2)+(4)
They do not ask you if the numbers are odd or even, they ask you if "n" is odd or even. In your examples n=7 and n=5
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-4,-2,0,2,4 are not consecutive. they skip numbers in between.
also N will always be odd, b/c you will always have zero as the median to get the the sum of consecutive numbers equal zero.
also N will always be odd, b/c you will always have zero as the median to get the the sum of consecutive numbers equal zero.