how many no. of images formed when three mirrors are placed at theta
60

We have studies that in two mirror system the number of images =360/q –1.

But in a three mirror system, the sum of the angles of the mirrors has to be 180° and mostly we go in for a 60–60–60 degree equilateral triangle.(other possibilities-45–45–45 and 30–60–90).

The number of images will be infinite and hope you have seen in your three mirror kaleidoscope.