pls help for explanation

[engg.manik]

55. Each segment from A to G has equal distance. Which of the following point represents [-(3^12)] ?

OA is D please can one explain how ???

[Brent@GMATPrepNow]

55. Each segment from A to G has equal distance. Which of the following point represents [-(3^12)] ?

OA is D please can one explain how ???

To determine the distance between each point we'll subtract 3^12 - 3^11 (i.e., G-F)
We can factor this to get 3^12 - 3^11 = 3^11 (3 - 1) = 2(3^11)
So, the distance between each point is 2(3^11)
So, to find E, we'll subtract F minus 2(3^11)
We get E = 3^11 - 2(3^11) = -(3^11) or -1(3^11)

To find point D, we'll subtract E minus 2(3^11)
We get -1(3^11) - 2(3^11) = -3(3^11) = -1[3(3^11)] = -1(3^12) or simply -(3^12)

So, the answer is D