A certain game board is in the shape of a non-convex polygon

This topic has expert replies
Moderator
Posts: 7187
Joined: Thu Sep 07, 2017 4:43 pm
Followed by:23 members

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

A certain game board is in the shape of a non-convex polygon, with spokes that extend from each vertex to the center of the board. If each spoke is 8 inches long, and spokes are used nowhere else on the board, what is the sum of the interior angles of the polygon?

(1) The sum of the exterior angles of the polygon is 360º.

(2) The sum of the exterior angles is equal to five times the total length of all of the spokes used.

OA B

Source: Manhattan Prep

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 2621
Joined: Mon Jun 02, 2008 3:17 am
Location: Montreal
Thanked: 1090 times
Followed by:355 members
GMAT Score:780

by Ian Stewart » Sat Mar 09, 2019 11:31 am

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

Statement 1 is always true, so is useless, while Statement 2 obviously gives you one equation in one unknown, so is sufficient.

But test takers don't need to know anything about 'exterior angles' for the GMAT, nor what a 'non-convex polygon' is, not to mention that Statement 2 is problematic because the quantities have different units, so this question is well out of the scope of the GMAT, and test takers can safely ignore it.
For online GMAT math tutoring, or to buy my higher-level Quant books and problem sets, contact me at ianstewartgmat at gmail.com

ianstewartgmat.com