By definition we have that the area of a regular octagon is:
A = 4.83L ^ 2
Where, L is the length of the octagon side.
the similarity ratio = the area ratio.
We have then:
similarity ratio = (50) / (18) = 25/9.
the ratio of the perimeters
A1 = 4.83L1 ^ 2
L1 ^ 2 = A1 / 4.83
L2 ^ 2 = A2 / 4.83
L1 ^ 2 / L2 ^ 2 = A1 / A2 = 25/9
L1 / L2 = 5/3
The perimeter is:
P1 = 8L1
P2 = 8L2
P1 / P2 = 8L1 / 8L2 = L1 / L2 = 5/3
answer:
similarity ratio:
25: 9
the ratio of the perimeters:
5: 3