If R, S, and T are points on a line, and if R is 5 meters from T and 2

Question

If R, S, and T are points on a line, and if R is 5 meters from T and 2 meters from S, how far is S from T ?

(1) R is between S and T.
(2) S is to the left of R, and T is to the right of R.

DS04602.0
OG2020 NEW QUESTION

avigutman · Accepted Answer

Video solution from Quant Reasoning:
 https://www.youtube.com/watch?v=lMqSrJ8gerY

Chethan92 · Answer

Each statement is individually Sufficient.

Refer to the attached figure.

D is the answer.

ZoltanBP · Answer

We know that  RT=5  and  RS=2 . The original question:  ST=?

1) We know that  R  is between  S  and  T . It doesn't matter whether  S  is to the left of  T  or  S  is to the right of  T  since  ST=RT+RS=5+2=7  in both cases. Thus, the answer to the original question is a unique value.  \implies   Sufficient

2) We can infer that  R  is between  S  and  T , so  ST=7  again. Thus, the answer to the original question is a unique value.  \implies   Sufficient

Answer: D

BrentGMATPrepNow · Answer

Given : R, S, and T are points on a line, and if R is 5 meters from T and 2 meters from S  
There are 4 possible scenarios that meet the above conditions: 
 https://i.imgur.com/kOeqUfZ.png

Target question :    How far is S from T?

Statement 1 : R is between S and T.  
When we check the 4 possible scenarios, we see that scenarios #2 and #3 meet the conditions of statement 1 
For both scenarios, the answer to the target question is  the distance from S to T is 7 
Since we can answer the  target question  with certainty, statement 1 is SUFFICIENT

Statement 2 : S is to the left of R, and T is to the right of R. 
When we check the 4 possible scenarios, we see that only scenario #2 meets the conditions of statement 2 
For scenario #2, the answer to the target question is  the distance from S to T is 7 
Since we can answer the  target question  with certainty, statement 2 is SUFFICIENT

Answer: D

Cheers,
Brent

ScottTargetTestPrep · Answer

We are given the distance from R to T and from R to S; and we need to determine the distance from S to T. To be able to determine the distance from S to T, we need to know in what order R, S and T are positioned on the line.

Statement One Alone:

R is between S and T.
Since R is between S and T, the distance between S and T is equal to the sum of the distances from R to T and from R to S. Since we are given both of those distances, we have enough information to calculate the distance from S to T. Statement one alone is sufficient.

Eliminate answer choices B, C and E.

Statement Two Alone:

S is to the left of R, and T is to the right of R.

Notice that this could only happen if R is between S and T. If R is not between S and T, either both S and T are to the left of R or both S and T are to the right of R. Since we know R is between S and T, we can proceed as in the previous statement to calculate the distance between S and T. Statement two alone is sufficient.

Eliminate answer choice A.

Answer: D

EMPOWERgmatRichC · Answer

Hi All,

We're told that R, S, and T are points on a line, R is 5 meters from T and R is 2 meters from S. We're asked for the distance between S and T. This question can be solved with a bit of logic and Arithmetic (and you might find it helpful to draw some actual number lines).

(1) R is between S and T.

With the information in Fact1, we know that R is somewhere between S and T. Regardless of where you place those 3 values on a number line, since R is 5 meters from S and 2 meters from T, then the line ST will be exactly 5+2 = 7 meters in length. 
Fact 1 is SUFFICIENT

(2) S is to the left of R, and T is to the right of R.

The information in Fact 2 takes the information that's in Fact1 and 'restricts' it a bit more (placing S to the 'left' and T to the 'right' - relative to R's position - on the number line. The deduction that we made in Fact1 also applies to Fact2. ST will be exactly 5+2 = 7 meters in length. 
Fact 2 is SUFFICIENT

Final Answer:  D

GMAT assassins aren't born, they're made, 
Rich

GMATinsight · Answer

Answer: Option D

Video solution by  GMATinsight

https://www.youtube.com/watch?v=51pg6UxfquI

bumpbot · Answer

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If R, S, and T are points on a line, and if R is 5 meters from T and 2

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GMAT Data Sufficiency (DS) Questions

If R, S, and T are points on a line, and if R is 5 meters from T and 2

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