Suppose the polygon is an N-sided polygon (first, the inner angle and formula of the polygon should be clear. Yes ((n-2)* 180). Now, let's find the unknown number n. ..

According to the meaning of the question, the degree of each inner angle is increased by 5 degrees, then we can get the final (that is, the largest) inner angle as follows.

120+5(n- 1), and then according to the angle ratio given by the condition, the equation can be listed as: (n-2) *180: [120+5 (n-1)].

You can find n=9!

So it's nine transformations.