If T is a set of more than two numbers, is
the sum of all the elements in set T equal
to zero?
(1) If n is in T, then -n is also in T.
(2) The number of negative numbers in
T equals the number of positive numbers
in T.
number theory
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Hi,
The question doesn't say distinct elements, so we can consider repetitions:
Consider the set, T = {2,4,4,-2,-2,-4} -> sum of elements is not equal to zero.
Consider the set, T = {2,4,6,-2,-4,-6} -> sum of elements is equal to zero.
Hence E
OA please?
The question doesn't say distinct elements, so we can consider repetitions:
Consider the set, T = {2,4,4,-2,-2,-4} -> sum of elements is not equal to zero.
Consider the set, T = {2,4,6,-2,-4,-6} -> sum of elements is equal to zero.
Hence E
OA please?
Cheers!
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Things are not what they appear to be... nor are they otherwise
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(1) If n is in T, then -n is also in T. - Numbers may repeat. Not sufficient.
(2) The number of negative numbers in T equals the number of positive numbers
in T. - No information on what numbers set contains. Not sufficient.
stmt 1 and 2 together - We know for every n there is -n and number of positive numbers is equal to number of negative numbers.
Hence, Sufficient.
(2) The number of negative numbers in T equals the number of positive numbers
in T. - No information on what numbers set contains. Not sufficient.
stmt 1 and 2 together - We know for every n there is -n and number of positive numbers is equal to number of negative numbers.
Hence, Sufficient.
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(1) If n is in T, then -n is also in T. Not suff
(2) The number of negative numbers in Not suff
We can not conclude both statements...
E
(2) The number of negative numbers in Not suff
We can not conclude both statements...
E
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HI Frankenstein -- If we consider the second statement then the case of repetition can be eliminated..Frankenstein wrote:Hi,
The question doesn't say distinct elements, so we can consider repetitions:
Consider the set, T = {2,4,4,-2,-2,-4} -> sum of elements is not equal to zero.
Consider the set, T = {2,4,6,-2,-4,-6} -> sum of elements is equal to zero.
Hence E
OA please?
total positives = total negatives
I think answer should be C ( BOTH STATEMENT TOGETHER ARE SUFFICIENT)
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Hi,saketk wrote:HI Frankenstein -- If we consider the second statement then the case of repetition can be eliminated..Frankenstein wrote:Hi,
The question doesn't say distinct elements, so we can consider repetitions:
Consider the set, T = {2,4,4,-2,-2,-4} -> sum of elements is not equal to zero.
Consider the set, T = {2,4,6,-2,-4,-6} -> sum of elements is equal to zero.
Hence E
OA please?
total positives = total negatives
I think answer should be C ( BOTH STATEMENT TOGETHER ARE SUFFICIENT)
The examples I have used satisfy both the conditions. Still we can't say that the sum of elements is zero. I don't understand how repetition is eliminated by 2nd statement.
{2,4,4,-2,-2,-4} and {2,4,6,-2,-4,-6} both satisfy statement (2). Still not enough to say whether sum is zero or not.
Cheers!
Things are not what they appear to be... nor are they otherwise
Things are not what they appear to be... nor are they otherwise
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yeah got it -- {5,-5,-5,6,6,-6} is an example -- Hence E is the answer.Frankenstein wrote:Hi,saketk wrote:HI Frankenstein -- If we consider the second statement then the case of repetition can be eliminated..Frankenstein wrote:Hi,
The question doesn't say distinct elements, so we can consider repetitions:
Consider the set, T = {2,4,4,-2,-2,-4} -> sum of elements is not equal to zero.
Consider the set, T = {2,4,6,-2,-4,-6} -> sum of elements is equal to zero.
Hence E
OA please?
total positives = total negatives
I think answer should be C ( BOTH STATEMENT TOGETHER ARE SUFFICIENT)
The examples I have used satisfy both the conditions. Still we can't say that the sum of elements is zero. I don't understand how repetition is eliminated by 2nd statement.
{2,4,4,-2,-2,-4} and {2,4,6,-2,-4,-6} both satisfy statement (2). Still not enough to say whether sum is zero or not.