gmatprep - list of postive integers
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Stmt I
list : -3 -2 -1
NO
list : 1 2 3
YES
INSUFF
Stmt II
list : 1 2 3 4
YES
list: -3 -2 -1 0
product is 0 which is non positive
INSUFF
Stmt I and II together
SUFF
C)
The product has to be positive since 0 cant be in the list (0 cant be the greatest number If the other numbers are negative or as the smallest number if the other numbers are positive since stmt I would be false as the product would be 0)
list : -3 -2 -1
NO
list : 1 2 3
YES
INSUFF
Stmt II
list : 1 2 3 4
YES
list: -3 -2 -1 0
product is 0 which is non positive
INSUFF
Stmt I and II together
SUFF
C)
The product has to be positive since 0 cant be in the list (0 cant be the greatest number If the other numbers are negative or as the smallest number if the other numbers are positive since stmt I would be false as the product would be 0)
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From 1 :
Highest and lowest product is +ve => 2 cases
1: Highest and lowest are -ve - can't say anything about the product of all integers inbetween and including them without knowing whether the number of integers is even or odd
2: Highest and lowest are +ve : Pretty straightforward , the product of all integers has to be positive.
So 1 is Suff
2 is clearly Insuff
Combining : If the number of integers are even - their product has to be positive - Suff, Hence C
Highest and lowest product is +ve => 2 cases
1: Highest and lowest are -ve - can't say anything about the product of all integers inbetween and including them without knowing whether the number of integers is even or odd
2: Highest and lowest are +ve : Pretty straightforward , the product of all integers has to be positive.
So 1 is Suff
2 is clearly Insuff
Combining : If the number of integers are even - their product has to be positive - Suff, Hence C