Jawabanmu

2014-04-26T17:55:40+07:00
Keliling=phi×2r | 62,8=3,14×2r | 2r=20 | r=10 semoga membantu^^
1 5 1
2014-04-26T17:58:54+07:00
Keliling lingkaran =  \pi . d
62,8 = 3,14 . d
62,8 / 3,14 = d
20 = d
r= 20/2 =10