goodyear2013
Which of the following cannot be true if the sum of k consecutive integers is 0?
I. The product of the k integers is positive
II. The smallest of the k integers is zero
III. The largest of the k integers is negative
A. I only
B. II only
C. III only
D. I and III
E. I, II and III
Explanation
(I) Because sum must be zero, series must include +ve & -ve numbers.
If series is -1, 0 and 1. Product will be zero, which is not +ve.
As any series of numbers we pick will have a product that is zero, product cannot be +ve
(Because integers must be consecutive, hence series must contain zero).
(I) cannot be true.
(II) Series could simply consist of integer 0.
(II) could be true.
(III) If largest integer is -1 → other integers must be -2, -3,….
Sum of these numbers could never be 0.
(III) cannot be true.
Which of the following cannot be true if the sum of k consecutive integers is 0?
I. The product of the k integers is positive
II. The smallest of the k integers is zero
III. The largest of the k integers is negativeA. I only
B. II only
C. III only
D. I and III
E. I, II and III
For the sum of k consecutive integers to be 0 we must have one of the following cases: {0}, {-1, 0, 1}, {-2, -1, 0, 1, 2}, ..., {..., -3, -2, -1, 0, 1, 2, 3, ...}.
I. The product of the k integers is positive. As you can see the product of the integers in either of these sets is always 0, thus I cannot be true.
II. The smallest of the k integers is zero. If the set is {0}, then it's possible.
III. The largest of the k integers is negative. As you can see the largest of the integers is always more than or equal to zero, thus III cannot be true.
Answer: D.
P.S. Overall the question is not good, because of the second option. I wouldn't expect GMAT to include a statement which is that ambiguous.
Hope you're doing great. Somehow, I don't agree with you considering {0} as the smallest number when there is only one integer in set, as question clearly states k consecutive "integers". Though, I agree that question certainly is ambiguous.
Hope not to see such Q in real GMAT.