a and b on the number line

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a and b on the number line

by tj123 » Mon May 25, 2009 10:32 pm
If a and b are nonzero numbers on the number line, is 0 between a and b?

1) The distance between 0 and a is greather than the distance between 0 and b

2) The sum of the distances between 0 and a and between 0 and b is greater than the distance between 0 and the sum a +b

OA B

[spoiler] i dont understand how B is sufficient a and b could also both be negative. For example: if a = -2 and b = -4, then the sum of the distances between 0 and a and between 0 and b is 6. Then the distance between 0 and the sum a +b = -6

B is sufficient if a and b are both negative or if one is positive and negative. answer should be e
[/spoiler]

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by ketkoag » Tue May 26, 2009 2:40 am
i think u've misinterpreted the second statement..
2ns state.. says the distance between 0 and sum a+b.
so firstly, no distance would be negative.
secondly, only if the 2 signs are opposite then only the second statement is true.
hence sufficient.
In your case both the distances are 6, but not 6 and -6. so they are equal. thus statement 2 is not satisfied by the values.

take 2 and -3, then by statement 2 distance between 2 and 0 is 2
distance between -3 and 0 is 3
distance between 2+(-3) = -1 and d 0 is 1.
hence by 2 we can get a uniques answer.
hence B is the answer..

HTH :)

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by aj5105 » Wed May 27, 2009 3:14 am
Right explanation above. Statement (2) is true only when a and b are on either side of 0.