Question 564681: how many regular polygons have an interior angle that measures between 100 and 149 degrees? Found 2 solutions by Alan3354, richard1234:Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! how many regular polygons have an interior angle that measures between 100 and 149 degrees?
----------
The exterior angles are between 31 and 80 degrees.
# of sides = 360/ext angle
360/32.7272 = 11 sides
360/36 = 10 sides
360/40 = 9 sides
360/45 = 8 sides
360/51.42 = 7 sides
360/60 = 6 sides
360/72 = 5 sides
-----------
7 polygons
You can put this solution on YOUR website! The sum of the degrees in an n-gon is 180(n-2), so for a regular polygon, the interior angle measure will be 180(n-2)/n. Therefore, we have
The "first" inequality yields .
The "second" inequality yields
Therefore, n is between 4.5 and 11.61; the only integer values of n that satisfy are 5, 6, ..., 11, or seven values.