If the sum of the interior angles of a regular polygon measures up to 1440 degrees, how many sides does the polygon have?
A. 10 sides
B. 8 sides
C. 12 sides
D. 9 sides
E. None of these
The OA is A.
I know that exist a formula to determine the number of sides 180(n-2) but is there another way to solve this PS question? Can any experts help, please? Thanks!
If the sum of the interior angles of a regular polygon...
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- BestGMATEliza
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I think the easiest way to solve this problem is to use the formula:
(n-2)*180=1440
1440/180=8=n-2
Therefore n=10
(n-2)*180=1440
1440/180=8=n-2
Therefore n=10
Eliza Chute
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Hi AAPL,
We're told that the sum of the interior angles of a regular polygon totals 1440 degrees. We're asked for the number of sides that the polygon has. There is one essential math rule that is required to answer this question - but there are a couple of different ways to consider the rule.
I often view the rule as "add a side, add 180 degrees"
3-sides = 180 degrees
4-sides = 360 degrees
5-sides = 540 degrees
6-sides = 720 degrees
Etc.
In this way, you just have to add 180s until you hit a total of 1440...Once you do that, you'll have the correct answer.
Final Answer: A
GMAT assassins aren't born, they're made,
Rich
We're told that the sum of the interior angles of a regular polygon totals 1440 degrees. We're asked for the number of sides that the polygon has. There is one essential math rule that is required to answer this question - but there are a couple of different ways to consider the rule.
I often view the rule as "add a side, add 180 degrees"
3-sides = 180 degrees
4-sides = 360 degrees
5-sides = 540 degrees
6-sides = 720 degrees
Etc.
In this way, you just have to add 180s until you hit a total of 1440...Once you do that, you'll have the correct answer.
Final Answer: A
GMAT assassins aren't born, they're made,
Rich
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- Scott@TargetTestPrep
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We can let n = the number of sides of the polygon and use the formula for the sum of the interior angles:AAPL wrote:If the sum of the interior angles of a regular polygon measures up to 1440 degrees, how many sides does the polygon have?
A. 10 sides
B. 8 sides
C. 12 sides
D. 9 sides
E. None of these
1440 = 180(n - 2)
1440 = 180n - 360
1800 = 180n
10 = n
Answer: A
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