What is the value of \(\dfrac{2t + t - x}{t - x}?\)

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Vincen wrote:
Mon May 31, 2021 8:08 am
What is the value of \(\dfrac{2t + t - x}{t - x}?\)

(1) \(\dfrac{2t}{t - x} = 3\)

(2) \(t - x = 5\)

Answer: A

Source: Official Guide
Target question: What is the value of (2t + t - x)/(t - x)?
This is a good candidate for REPHRASING the target questions.
We'll use the fact that (a + b)/c = a/c + b/c
Likewise, (2t + t - x)/(t - x) = 2t/(t - x) + (t - x)/(t - x)
= 2t/(t - x) + 1
At this point, we can see that we really just need to find the value of 2t/(t - x)
REPHRASED target question: What is the value of 2t/(t - x)?

Statement 1: 2t/(t - x) = 3
Perfect! This is EXACTLY the information we need!
Since we can answer the REPHRASED target question with certainty, statement 1 is SUFFICIENT

Statement 2: t - x = 5
There are several values of t and x that satisfy statement 2. Here are two:
Case a: t = 5 and x= 0, in which case 2t/(t - x) = 5
Case b: t = 6 and x= 1, in which case 2t/(t - x) = 12/5
Since we cannot answer the REPHRASED target question with certainty, statement 2 is NOT SUFFICIENT

Answer: A
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