Last visit was: 25 Apr 2026, 05:54 It is currently 25 Apr 2026, 05:54
Home
Messages
Tests
Schools
Events
Close
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel
Back to Forum
Create Topic
505-555 (Easy)|   Geometry|      
User avatar
pzazz12
User avatar
Joined: 22 Sep 2010
Last visit: 25 Oct 2010
Posts: 59
Own Kudos:
1,251
 [4]
Posts: 59
Kudos: 1,251
 [4]
If the sum of the interior angles of a regular polygon measures up to 05 Oct 2010, 05:40
Kudos
Add Kudos
4
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
A
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

15% (low)

Question Stats:

74% (00:55) correct 26% (01:13) wrong based on 292 sessions

History

Date
Time
Result
Not Attempted Yet
If the sum of the interior angles of a regular polygon measures up to 1440 degrees, how many sides does the polygon have?

1. 10 sides
2. 8 sides
3. 12 sides
4. 9 sides
5. None of these
ShowHide Answer
Official Answer
A
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 25 Apr 2026
Posts: 109,826
Own Kudos:
811,172
 [2]
Given Kudos: 105,878
Products:
GMAT Club Tests Forum Quiz
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,826
Kudos: 811,172
 [2]
If the sum of the interior angles of a regular polygon measures up to 05 Oct 2010, 06:18
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
pzazz12
If the sum of the interior angles of a regular polygon measures up to 1440 degrees, how many sides does the polygon have?

1. 10 sides
2. 8 sides
3. 12 sides
4. 9 sides
5. None of these
Show more

Sum of Interior Angles of a polygon is \(180(n-2)\) where \(n\) is the number of sides.

So \(180(n-2)=1440\) --> \(n=10\).

Answer: A.

For more on this check Polygons chapter of Math Book: math-polygons-87336.html

Hope it helps.
avatar
ketangada
avatar
Joined: 30 Sep 2010
Last visit: 12 Oct 2010
Posts: 1
Posts: 1
Kudos: 0
If the sum of the interior angles of a regular polygon measures up to 05 Oct 2010, 06:19
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hi

The formula for interior angle is (n-2)*180

(10-2)*180 = 1440.

Answer choice 1 is correct.
avatar
Marshmallow
avatar
Joined: 29 Sep 2010
Last visit: 30 Oct 2013
Posts: 12
Own Kudos:
32
Given Kudos: 1
Schools: IMD '16 (A)
GMAT 1: 730 Q47 V44
Schools: IMD '16 (A)
GMAT 1: 730 Q47 V44
Posts: 12
Kudos: 32
If the sum of the interior angles of a regular polygon measures up to 05 Oct 2010, 06:56
Kudos
Add Kudos
Bookmarks
Bookmark this Post
If you don't know the formula you can get to the answer this way. A little more involved but probably still doable in the crunch:

Start with the second to highest number in the answers (i.e. 10) so you can go higher or lower depending on what you find.

Draw or visualize a decagon, and run the five diagonals that go through the center, so that you end up with 10 identical 'wedges' or 'pizza slices' which will be isosceles triangles.

All 10 triangles will have the center, where all diagonals cross, in common. You know the sum of all those angles is 360, so since you have 10 of them, that angle is 360/10 = 36 for each triangle. Now you can see that for each slice, the sum of the other triangles must be 180 - 36 = 144. Therefore, since you have 10 triangles, the total sum of the angles that make the decagon is 144 *10 = 1440. Voila.

If this had been too low, you know the polygon would have to have more sides, if it had been too big, you would need less. so you could work that way.

Still, formula is MUCH simpler so this tells me I need to brush up!!
User avatar
tingle15
User avatar
Joined: 15 Apr 2010
Last visit: 02 Oct 2011
Posts: 82
Own Kudos:
352
 [1]
Given Kudos: 3
Posts: 82
Kudos: 352
 [1]
If the sum of the interior angles of a regular polygon measures up to 05 Oct 2010, 12:15
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Sum of interior angles of a regular polygon = 180 * (n-2), where n is the number of sides.

180 * (n-2) = 1440.

Solve for n.

Answer = 10 sides
User avatar
BrentGMATPrepNow
User avatar
Major Poster
Joined: 12 Sep 2015
Last visit: 31 Oct 2025
Posts: 6,733
Own Kudos:
36,462
 [1]
Given Kudos: 799
Location: Canada
Expert
Expert reply
Posts: 6,733
Kudos: 36,462
 [1]
If the sum of the interior angles of a regular polygon measures up to 19 Jan 2018, 14:01
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
pzazz12
If the sum of the interior angles of a regular polygon measures up to 1440 degrees, how many sides does the polygon have?

1. 10 sides
2. 8 sides
3. 12 sides
4. 9 sides
5. None of these
Show more

Nice rule: The sum of the interior angles in an N-sided polygon is equal to 180(N - 2) degrees

So, we can write: 180(N - 2) = 1440
Divide both sides by N-2 to get: N-2 = 8
Solve: N = 10

Answer: A

Cheers,
Brent
avatar
ams3212
avatar
Joined: 24 Aug 2017
Last visit: 10 Aug 2020
Posts: 3
Own Kudos:
6
Given Kudos: 17
GPA: 3.14
Posts: 3
Kudos: 6
If the sum of the interior angles of a regular polygon measures up to 08 May 2019, 12:25
Kudos
Add Kudos
Bookmarks
Bookmark this Post
this is my answer
we know that the sum of the angles is 1440
and we should use the formula that the sum of the angles = 180*(n-2)
1440=180*(N-2)=> 180N=1800 N= 10.
so the answer is A (10)
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,981
Own Kudos:
1,117
Posts: 38,981
Kudos: 1,117
If the sum of the interior angles of a regular polygon measures up to 05 Aug 2023, 10:05
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Automated notice from GMAT Club BumpBot:

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

This post was generated automatically.
Moderators:
Bunuel
Math Expert
109826 posts
Krunaal
Tuck School Moderator
852 posts