GMAT prep DS question

[mlane25269]

Can some explain this question? Thanks!

[niraj_a]

the simple answer to this one that i know of is that no part of the statements given ever tell what is really in the set to begin with....

[mlane25269]

But if that's really the case then wouldn't the answer be "E"? The OA is C.

[Nycgrl]

OA is C...its a very tricky questions

statment 1......product of smallest and greatest number is +ve.Now it can be 2 and 10 or -2 and -10 in both the cases product will be positive.but we don't know how many numbers are there between theses two numbers-----insuff

2nd --list has even numbers-----in sufff

1&2 together

since product of smallest and greatest number is postive means both have same signs. if all the numbers are positive then it doesnt matter whether the total number of numbers in list are even or odd...BUT if all the numbers are -ve in that case for the product to be positive there should be even number of numbers on list. -*- =+

[mlane25269]

But suppose I have -2*-2*2*-2 (three negative value and 1 positive value) then the answer would be -10 right?

Yet if I have -2*2*2*-2 (two negatives and two positive values) then my answer is +10.

So would the answer still be "C" even though the example above is not a definite "Yes" or "No" as is the case with Data Sufficiency questions?

[Stuart@KaplanGMAT]

But suppose I have -2*-2*2*-2 (three negative value and 1 positive value) then the answer would be -10 right?

Yet if I have -2*2*2*-2 (two negatives and two positive values) then my answer is +10.

So would the answer still be "C" even though the example above is not a definite "Yes" or "No" as is the case with Data Sufficiency questions?

No, because you haven't followed the rules.

(1) says the product of the greatest and smallest numbers in the list is positive.

In both examples you give, the smallest is -2 and the biggest is +2, which have a product of -2. Therefore, neither example you cite is valid.

The takeaway from (1) is that the list must be all positives or all negatives.

And.. not that it's relevant to your point, but your multiplication is way off too! (2^4 = 16, not 10)

[mlane25269]

ok I'm still confused because neither of the statements give any information about the values in between the greatest and the smallest integers.

If I have 1*-1*1*1 wouldn't that make the entire product negative even though there is only one negative value?

[Nycgrl]

Read the question carefully......In ur example 1,-1,1,1,1 which is GREATEST of all. There can be only one greatest number

[mlane25269]

ok I see now. Thanks, Nycgirl