Answer:
Number of sides of a regular polygon whose smallest angle of rotation is
is 20. so correct option is 20.
Solution:
Need to determine sides of a regular polygon having smallest angle of rotation as
In above case smallest angle of rotation is same as central angle of regular polygon.
So now we need to determine number of sides of regular polygon whose central angle is
![18^(\circ)](https://img.qammunity.org/2020/formulas/mathematics/high-school/fncl7qzg281sn04kfb4ase3fob3gcjmhme.png)
Number of sides of regular polygon
![= \frac{360}{\text {central angle}}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/i2kdboqy859g14bgh7fix3iumnl4w52508.png)
So for a regular polygon having central angle =
Number of sides =
![(360)/(18) = 20](https://img.qammunity.org/2020/formulas/mathematics/middle-school/lilidn2ol5r7614zbzhu2hjvl25mp7k2jh.png)
Hence number of sides of a regular polygon whose smallest angle of rotation is
is 20.