There are many possible solutions to this problem.
Area (A) = Length (L) x width (w)
200 = L x w (any two numbers whose product is 200 is acceptable)
I am going to choose L=20 and w=10, then A = 20 x 10 = 200
Perimeter (P) = 2L + 2w
= 2(20) + 2(10)
= 40 + 20
= 60
Answer: one possible solution is L=20, w=10, P=60