tolong kerjakan no 11 pake cara makasih

l = 729 : 81 = 9 m = 900 cm
p = 81 m = 8100 cm
tebal pagar = 30 mm = 3 cm
---JAWABAN---
p = 8100 - 3 = 8097 cm
l = tetap sama
keliling = 8097 x 2 + 900 x 2 = 17994 cm
luas = 8097 x 900 = 7287300 cm^2
keliling awal : keliling akhir = 18000 : 17994 = 3000 : 2999
---Maaf kalau salah---