Question 1063188
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a regular polygon of n-sides is such that each interior angle is 120 degree greater than the exterior angles. find
1. the value of n
2. the sum of all the interior angled.
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<pre>
A + B = 180,
A - B = 120

=====> A = 150 degs (interior angle);  B = 30 degs (exterior angle).

====>  n = {{{360/30}}} = 12.


The sum of all interior angle of a polygon is 360 degs always (in all regular cases).
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