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
