Jawabanmu

2014-06-13T19:24:15+07:00
P=nxk
400/80=k
5m=k
5000cm=k

k=2xpixr
5000/2.3,14=r
796,17cm=r

5/6,28=0,79617.......

5 m = 500 cm
diket : n = 80 kali
J = 400m
ditanya : r ?
jawab : K = J : n
400m : 80 kali
= 5 m = 5000 cm
K = 2 X Pi X R
5000 cm = 2 X 3,14 X R
r = 5000 cm : (2 X 3,14)
= 796, 178 cm
5 m = 500 cm bukan 5000 cm
2014-06-13T23:01:13+07:00
P=nxk
400/80=k
5m=k
k=2xpixr
5000/2,3,14=r
796,17cm=r
5/6,28=0,79617