Is y between -2 and 1 on the number line?

Question

(1) y is to the right of -1 on the number line.
(2) y is to the left of 2 on the number line.

saswata4s · Accepted Answer

Is -2<y<1?

(1) y is to the right of -1 on the number line;
That means -1<y.

But y can be 0 and also y can be 3.
y= 0 satisfies -2<y<1, but y= 3 not. Hence, Insufficient.

(2) y is to the left of 2 on the number line;
That means y<2.

y can be 0 and also y can be -3.
y= 0 satisfies -2<y<1, but y= -3 not. Hence, Insufficient.

(1) & (2) together,
-1<y<2

y can be 0 and also y can be 1.
y= 0 satisfies -2<y<1, but y= 1 not. Hence, Insufficient.

Answer E.

Prasannak · Answer

Hi ,
 In reference to above question - Does Number line always mean that It is obvious that we are talking about integers .
because Although I got the answer correct the only reason I eliminated both together as Insufficient is because It was NOT mentioned that y is an integer so left of 2 can also mean 1.5 right?

Bunuel · Answer

A number line consists of all numbers, not only integers but also fractions and irrational numbers. So, you are right, you can consider y to be 0.5 and 1.5 to get two different answers to the question.

Madhavi1990 · Answer

Hello! Request some light on the wording. the questions says 
"Is  y between -2 and 1  on the number line?

1. y is to the right of -1 on the number line.
2. y is to the left of 2 on the number line"

Now as per 1) + 2) = -1<y<2 so Y is INBETWEEN the values. So I picked C as it is sufficient. But as per OA it is asking for a specific value, which of course it doesn't tell, hence E is right. So if a question comes similar to this, are we to pick the correct value or just answer the question stem (here: is it in between or not).
Thank you!

Bunuel · Answer

The question does not ask for the value of y.

The question asks: is -2 < y < 1. We got that -1 < y < 2 (which is not the same as -2 < y < 1). If y = 0, then the answer is YES but if y = 1.5 then the answer is NO.

Madhavi1990 · Answer

Thank you, it really helped clear up a concept - I'll be using this to write the question better.

Kinshook · Answer

Asked: Is y between -2 and 1 on the number line? (1) y is to the right of -1 on the number line. y>-1 y may or may not be <1 NOT SUFFICIENT (2) y is to the left of 2 on the number line. y<2 y may or may not be >-2 NOT SUFFICIENT Combining (1) & (2) 2>y>-1 NOT SUFFICIENT IMO E Posted from my mobile device

Gella · Answer

The question is asking whether y is between -2 and 1 and the statements should be able to answer "yes" or "no". Hence combining both statements we get that y is between -1 and 2 and this answers the question that y is not between -2 and 1. Isn't it?

Bunuel · Answer

There are two types of data sufficiency questions:

1. YES/NO DS Questions:

In Yes/No Data Sufficiency questions, a statement is sufficient if the answer is always "yes" or "no", whereas a statement is insufficient if the answer can be "sometimes yes" and "sometimes no".

2. VALUE DS QUESTIONS:

When a DS question asks about the value of some variable, then the statement is sufficient ONLY if you can obtain a single numerical value for this variable.

The question at hand belongs to the first category. For a statement to be sufficient, we should get a definite YES or a definite NO answer to the question, which asks "is -2 < y < 1?" When combining the statements, we get that -1 < y < 2. Now, y is a specific number, so if y = 0, then the answer is YES, y IS between -2 and 1 on the number line. However, if y = 1.5, then the answer is NO, y is NOT between -2 and 1 on the number line. Thus, we don't have a definite answer to the question, which means that the statements are insufficient and the answer is E.

To represent this visually, the question asks whether y falls within the green zone shown below:

----(-2) --(-1)----- 1--2----

Upon combining the statements, we deduce that y falls somewhere within the blue zone shown below:

----(-2)--(-1) -----1-- 2----

As you can observe, y might or might not fall within the green zone, which indicates that the statements, when taken together, are insufficient.

Hope it's clear.

Gella · Answer

Thank you so much for the explanation. Now it's clear.

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Is y between -2 and 1 on the number line?

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GMAT Data Sufficiency (DS) Questions

Is y between -2 and 1 on the number line?

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