Question

if this regular decagon is rotated counterclockwise by 3 times the smallest angle of rotation, which vertex will be in the top position? c d e f

Explanation:

Step1: Calculate the smallest angle of rotation

For a regular decagon, the smallest angle of rotation is $\frac{360^{\circ}}{10} = 36^{\circ}$.

Step2: Determine the vertex after rotation

Rotating counter - clockwise 3 times the smallest angle ($3\times36^{\circ}=108^{\circ}$).
Starting from vertex B, moving 3 positions counter - clockwise (B→C→D→E). So vertex E will be in the top position.

Answer:

E