Bunuel
abhisheknandy08
Hi Bunuel ,
Could you post the detail solution for this question .
Regards,
Is the average of n consecutive integers equal to 1 ?Any set of consecutive integers is an evenly spaced set, where mean = median. Thus for the average to be 1 we should have one of the following types of sets:
{1}
{0, 1, 2}
{-1, 0, 1, 2, 3}
So, basically there should be equal number of elements less than 1 and greater than 1. You can notice that in this case the number of elements turns out to be odd.
(1) n is even --> n is not odd --> 1 cannot be the average. Sufficient.
(2) if S is the sum of the n consecutive integers, then 0 < S < n --> divide by n: 0 < S/n < 1. Since S/n (the sum of the elements divided by the number of elements) is the average, then we directly got that the average is not 1, it's < 1. Sufficient.
Answer: D.
Hope it's clear.
BunuelI thought that we can only work with manipulating the inner term (e.g., s) in this case per my question above for Karishmab
In other words, if I have: 5 < x+2 < 9
Can you do the following for division? Dividing all terms by 5 --> 1 < (x+2)/5 < 9/5
Dividing all terms by x+2 --> x/(x+2) < 1 < 9/(x+2)
Dividing all terms by 9 --> 5/9 < (x+2)/9 < 1
Can you do the following for subtraction?Again, if I have: 5 < x+2 < 9
Subtracting 9 from all terms --> -4 < x-7 < 0
Subtracting x+2 from all terms --> -x+3 < 0 < -x-2
and vice versa for multiplication?
Many thanks
KarishmaB