Comprehension Passage
Directions: Study the following information carefully and answer the given questions:
An input-output is given in different steps. Some mathematical operations are done in each step. No mathematical operation is repeated in next step.

As per the rules followed in the steps given above, find out in each of the following questions the appropriate steps for the given input.

What is the highest number obtained in all the step?
1
16
2
24
3
36
4
20
5
25