Number line - B

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Number line - B

by tanyajoseph » Sat Sep 01, 2007 10:57 am
If a and b are nonero nos on the no line, is 0 between a and b?

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

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by montz » Sun Sep 02, 2007 9:49 am
1) The dist between 0 and a is greater than the dist between 0 and b.

a and b both can be negative, both can be positive or one positive and one negative and still satisfy the condition in statement 1. NOT Sufficient

(For eg: a = -3, b = -2 or a = 3, b = 2 or a = -3, b = 2)

* The distance between 0 and any number (positive or negative) on the number line will always be positive or in other words we take the absolute value.

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

This can be written as |a| + |b| > |a+b| , which can only be true if either a or b is negative. If both are positive or both are negative then
|a| + |b| = |a+b|

Hence 2 alone is sufficient.

Is B not the right answer?