<PRE><B>Question 277787</B>
Hello, 
There is a formula to follow which is:
(n-2)180=total interior angle degrees. So we can plug in the known value:
(n-2)180=3240 Rewritten as:
180n-360=3240 Add 360 to both sides and divide by 180 to get:
n=20 
There we go, 20 sides. 
Make sense? 
RJ 
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