How do you show your work for four girls and two boys are working on a project. they have four square pieces of felt. if each person getsan equal share of the felt how muchof a piece of felt will each person get

The perimeter of ? cde is 55 cm. a rhombus dmfn is inscribed in this triangle so that vertices m, f, and n lie on the sides cd , ce , and de respectively. find cd and de if cf=8 cm and ef=12 cm. the answer is not cd=20 and de=15. i have tried that one, it does not work.