The number of images formed = 360n\;\frac{360}{n}n360 where the value gotten is odd
else, = 360n−1\;\frac{360}{n} - 1n360−1.
Solving, we have that 36020=18\;\frac{360}{20} = 1820360=18
Hence, the no of images formed is 18 - 1 = 17.
