BTGmoderatorDC wrote:If x + y + z > 0, is z > 1?
(1) z > x + y + 1
(2) x + y + 1 < 0
Inequalities can be ADDED TOGETHER.
One condition:
Before two inequalities can be added together, the inequality symbol must face the SAME DIRECTION in each inequality.
Statement 1:
Adding together x+y+z > 0 and z > x+y+1, we get:
x+y+z+z > 0+x+y+1
2z > 1
z > ½
If z = ¾, the answer to the question stem is NO.
If z = 2, the answer to the question stem is YES.
INSUFFICIENT.
Statement 2:
Inequality in the question stem:
x+y+z > 0
If we reverse x+y+1 < 0, we get:
0 > x+y+1
Since the inequality symbol is facing the same direction in the two blue inequalities, they can now be added:
x+y+z+0 > 0+x+y+1
z > 1
Thus, the answer to the question stem is YES.
SUFFICIENT.
The correct answer is
B.
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