Hector wants to tile his rectangular shed floor with rubber towels he found a company that will custom tile square 60 by 60. The length of the shed floor is 240 inches and the roof is 140 inches. What is the size length of the largest square tile Hector can use to tile the shed for so that there are no gaps or relapse in the entire floor is covered. The side length of the largest square tile Hector can use to tile his full shed is how many tile will have to need to cover his shed floor?