If 75% is £45 then what is the full cost

What is the size of the matrix resulting from

Any is very appreciated! (picture is provided below)not sure how to do this at all won't lie

In the triangles, tr = ge and sr = fe. if = 3.2 ft, which is a possible measure of ? 1.6 ft 3.0 ft 3.2 ft 4.0 ft