If you were going to make segments marks on a chewy fruit worm without any marks what would be the advantage or disadvantage of using a prime number of segments

The length of a rectangular board is 3 feet less than twice its width. a second rectangular board is such that each of its dimensions is the reciprocal of the corresponding dimensions of the first rectangular board. if the perimeter of the second board is one-fifth the perimeter of the first, what is the perimeter of the first rectangular board?