A) 10
B) 15
C) 20
D) 25
Correct Answer: C
Solution :
If the number of sides of the regular polygon be n, then \[\therefore \] \[\left( \frac{2n-4}{n} \right)\times 90=8\times \frac{4\times 90{}^\circ }{n}+18\] \[\left( \frac{2n-4}{n} \right)\times 5=\frac{160}{n}+1\] \[\Rightarrow \] \[10=n-20=160+n\] \[\Rightarrow \] \[10n-n=180\] \[\Rightarrow \] \[9n=180\] \[\Rightarrow \] \[n=20\]You need to login to perform this action.
You will be redirected in
3 sec