What is the value of r?

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What is the value of r?

by nakul_anand » Sun May 02, 2010 5:12 pm
If m and r are two numbers on a number line, what is the value of r?

(1) The distance between r and 0 is three times the distance between m and 0.

(2) 12 is half way between m and r

[spoiler]OA:E[/spoiler]

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by liferocks » Sun May 02, 2010 5:33 pm
Clearly either of the condition alone is not sufficient.Combining
From 1,
m=x and r=3x
hence distance between m and r is=2x...when m,r are on the same side of number line
or 4x...when m,r are on the opp side of number line

From 2,
from this also we cannot conclude anything about absolute value of neither m nor r .Also distance between them is unknown.

both together alos not suff

Ans E
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by tpr-becky » Sun May 02, 2010 8:25 pm
from stmnt 1 we can't conclude any numbers, only the relationship between m and r. (this also makes me think about postive and negative so it is really that the /m/ is 3 times the /r/

For stmt 2 we now know that 12 is the average of m and r (if both are positive and the average of the absolute values if one is negative) but we can't tell what the numbers would be.

if we combine them we don't know anything further because we still have no indication of whether the numbers are positive or negative.

So E.
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by gmatmachoman » Tue May 04, 2010 5:56 am
nakul_anand wrote:If m and r are two numbers on a number line, what is the value of r?

(1) The distance between r and 0 is three times the distance between m and 0.

(2) 12 is half way between m and r

[spoiler]OA:E[/spoiler]
Guys, if we take M=6 & R=18, I see both conditions are used and satisfy them .

IMO C...


any thoughts on this??

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by tpr-becky » Tue May 04, 2010 9:41 am
Finding numbers that work doesn't mean that you have a value for R - the values of m=-12 and r=36 also work for both statements therefore we have r=18 or r=36 which doesn't solve a value problem.
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by gmatmachoman » Tue May 04, 2010 11:51 am
tpr-becky wrote:Finding numbers that work doesn't mean that you have a value for R - the values of m=-12 and r=36 also work for both statements therefore we have r=18 or r=36 which doesn't solve a value problem.
ooops!! I am sorry!