Given : Each interior angle is 165∘
Let each exterior angle be x.
Now, Each exterior angle+Each interior angle=180∘
∴ 165∘+x=180∘
x=180∘−165∘
=15∘
So, each exterior angle is 15∘
Also , each exterior angle =360∘n
15∘=360∘n
∴ n=360∘15∘
∴ n=24
So ,the number of sides is 24.