Number line

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Number line

by psm12se » Sun Mar 03, 2013 7:29 am
The points A, B, C, and D are on a number line, not necessarily in that order. If the distance between A and B is 18 and the distance between C and D is 8, what is the distance between B and D?

1. The distance between C and A is the same as the distance between C and B.
2. A is to the left of D on the number line

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by Anurag@Gurome » Sun Mar 03, 2013 8:15 am
psm12se wrote:The points A, B, C, and D are on a number line, not necessarily in that order. If the distance between A and B is 18 and the distance between C and D is 8, what is the distance between B and D?

1. The distance between C and A is the same as the distance between C and B.
2. A is to the left of D on the number line
Statement 1: This means C is the midpoint of AB, AC = BC = 9
Hence, possible scenarios are...
  • A--D---C-----B --> In this case BD = BC + CD = 9 + 8 = 17
    A-----C---D--B --> In this case BD = BC - CD = 9 - 8 = 1
Not sufficient

Statement 2: Not enough to conclude anything.

Not sufficient

1& 2 Together: No new information as from the conclusion of statement 1 we know that A is to the left of D on the number line.

Not sufficient

The correct answer is E.
Anurag Mairal, Ph.D., MBA
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