If r is represented by the decimal 0.t5 what is the digit ?

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1) r< 1/3
2) r < 1/10

Original Answer is B, cause its only satisfied for 0.09 - 0.01 -> therefore t=0

I thought, that it is also possible, that r is negative, because its not stated in the question. so possible solution would be -0,95, -0.85...and therefore its NOT sufficient -> E

Or is this a defintion by the GMAT ?

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by Atekihcan » Tue May 07, 2013 9:05 pm
If r is represented by the decimal 0.t5 what is the digit t?
There is no minus sign in that representation.
So, r cannot be negative.

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by Brent@GMATPrepNow » Wed May 08, 2013 6:41 am
peterpong wrote: If r is represented by the decimal 0.t5 what is the digit t?
1) r < 1/3
2) r < 1/10
NOTE: I added "t" to the target question (as per the original question)

Target question: What is the digit t?

Given: r = 0.t5

Statement 1: r < 1/3
So, 0 < r < 0.3333...
In other words, 0 < 0.t5 < 0.3333...
So, t could equal 0, 1, or 2
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT

Statement 2: r < 1/10
So, 0 < r < 0.1
In other words, 0 < 0.t5 < 0.1
So, t must equal 0
Since we can answer the target question with certainty, statement 2 is SUFFICIENT

Answer = B

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Brent
Brent Hanneson - Creator of GMATPrepNow.com
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