Carcass wrote:
Attachment:
GRE Points X, Y, and Z lie on a map as shown.png
Points X, Y, and Z lie on a map as shown in the diagram. The distance from X to Y is 13 miles and the distance from Y to Z is 5 miles. If a person walks from X to Y, and then from Y to Z, approximately how many miles longer would that person walk than a person who walks directly from X to Z ?
A. 2
B. 3
C. 4
D. 5
E. 6
We have \(XZ^2 = XY^2 + YZ^2\) from the Pythagorean Theorem.
Since we have \(XY = 13\) and \(YZ = 5\), we have \(XZ = \sqrt{13^2 + 5^2} = \sqrt{169+25} = \sqrt{194} ≒ \sqrt{196} = \sqrt{14^2} = 14\).
The question ask the approximation of \(XY + YZ - XZ = 13 + 5 - \sqrt{194} ≒ 18 - 14 = 4\).
Therefore, C is the right answer.