keliling lingkaran 77cm pi 22/7 berapa diameter

[tex] \:keliling \: lingkaran = \: \pi \: d[/tex]
77 = 22/7.d
d=7/22.77
d=3,5.7
d=24,5

k = 2πr
77 = 2.22/7.r
77x7/44 = r
12.25 =r
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