Is x+y > 0?
(1) x > y
(2) x + y -1 >0
The OA is the option B.
Why is not sufficient the first statement? Also, why is sufficient the second one? I need a clarification here. Thanks in advance.
Is x+y > 0?
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Hi M7MBA.M7MBA wrote:Is x+y > 0?
(1) x > y
(2) x + y -1 >0
The OA is the option B.
Why is not sufficient the first statement? Also, why is sufficient the second one? I need a clarification here. Thanks in advance.
Let's take a look at your question.
First statement
Here, we can have the following cases:(1) x > y
- x=1 and y=0, then x+y=1 > 0. YES
- x=1 and y=-5, then x+y=-4 < 0. NO
Hence, this statement is NOT SUFFICIENT.
Second statement
Here, if we solve for x and y we get: $$x+y-1>0\ \ \ \Rightarrow\ \ \ x+y>1>0.\ \ \ \ \ YES.$$ Therefore, this statement is SUFFICIENT.(2) x + y -1 >0
In conclusion, the correct answer is the option B.
I hope it helps.
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Target question: Is x+y > 0?M7MBA wrote:Is x+y > 0?
(1) x > y
(2) x + y -1 > 0
Statement 1: x > y
Let's TEST some values.
There are several values of x and y that satisfy statement 1. Here are two:
Case a: x = 2 and y = 1 (this satisfies the condition that x > y). In this case, x + y = 2 + 1 = 3. So, the answer to the target question is YES, x+y IS greater than 0
Case b: x = 0 and y = -1 (this satisfies the condition that x > y). In this case, x + y = 0 + (-1) = -1. So, the answer to the target question is NO, x+y is NOT greater than 0
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: x + y -1 > 0
First recognize that x + y > x + y - 1, we can now say: x + y > x + y - 1 > 0
Now, if we ignore the x + y - 1 part, we can see that x + y > 0
So, the answer to the target question is YES, x+y IS greater than 0
Since we can answer the target question with certainty, statement 2 is SUFFICIENT
Answer: B
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Statement One Alone:M7MBA wrote:Is x+y > 0?
(1) x > y
(2) x + y -1 >0
x > y
Statement one alone is not sufficient to answer the question. For example, if x = 2 and y = 1, then x + y > 0. However, if x = -1 and y = -2, then x + y is not greater than 0.
Statement Two Alone:
x + y - 1 > 0
We see that x + y > 1. If x + y > 1, then x + y > 0. Statement two alone is sufficient to answer the question.
Answer: B
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