So i'm doing a princeton review online quiz and this just doesnt seem right to me. (This is DS)
If a is an integer, is a > 0?
(1) (7a – 6a) is a positive number.
(2) a – 2 is a negative number.
The quiz says that statement one alone is suff. But I think neither is suff. If a=0 then for (1) then you get a positive #, just as if a were greater than 0. And since zero is an integer - why is my answer incorrect? Please help out as I am just starting to get the hang of DS and now im trying not to be discouraged by this logic.
am i nuts or is this wrong?
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zero is neither positive not negative. So, a=0 does not apply for (1)ramasterre wrote:So i'm doing a princeton review online quiz and this just doesnt seem right to me. (This is DS)
If a is an integer, is a > 0?
(1) (7a – 6a) is a positive number.
(2) a – 2 is a negative number.
The quiz says that statement one alone is suff. But I think neither is suff. If a=0 then for (1) then you get a positive #, just as if a were greater than 0. And since zero is an integer - why is my answer incorrect? Please help out as I am just starting to get the hang of DS and now im trying not to be discouraged by this logic.
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But isnt it sayin 7a-6a is positive, not actually referencing a itself but the entire equation? Or am i reading it wrong?
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Well, you are given that (7a – 6a) is a positive number. So, youramasterre wrote:But isnt it sayin 7a-6a is positive, not actually referencing a itself but the entire equation? Or am i reading it wrong?
have to exclude a=0. Else (1) will not hold true.
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7a - 6a is positive translates to 7a - 6a > 0, or a>0. It is not referring to any equation. It just means the expression 7a - 6a is greater than 0. the expression 7a - 6a can be simplified to a, so a>0.ramasterre wrote:But isnt it sayin 7a-6a is positive, not actually referencing a itself but the entire equation? Or am i reading it wrong?
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Oh! so if you simplify then its saying 1a>0 which means a >0. Ok thank you!! Sometimes you just need a different perspective