Jawabanmu

2014-06-19T20:00:10+07:00
22m=2200cm

25keliling= 25 x d x 22/7
2200 = 25 x d x 22/7
d= 2200 : 25 x 7/22
d= 28
r= 14 cm

trus dicari luas permukaan rodanya. 

2014-06-19T21:02:34+07:00
22m = 2200cm
kell. roda = 2200 : 25 = 88 cm
88cm = 22/7 x d
d= 88 x 7/22 = 28 cm
r = 1/2d = 14 cm
luas permukaan roda = n x r x r = 22/7 x 14 x 14 = 616 cm2

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