Hitunglah keliling lingkaran jika diketahui a. jari - jari 49 m b. jari - jari 21 m c. jari - jari 5 cm d. jari - jari 12 cm e. jari - jari 10,5 cm f. diameter

K = 2 × phi × r
a. 2(22/7)(49)
= 308 m

b. 2(22/7)(21)
= 132 m

c. 2(3,14)(5)
= 31,4 cm

d. 2(3,14)(12)
= 75,36 cm

e. 2(22/7)(10,5)
= 66 cm

K = d × phi

f. 70(22/7)
= 220 cm

g. 2,8(22/7)
= 8,8 cm

h. 15(3,14)
= 47,1 m

i. 50(3,14)
= 157 m

j. 2,4(3,14)
= 7,536 cm

Please, let me answer your question :)
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Mapel : Matematika
Tentang : Bangun Datar
Pembahasan :

K = 2πr
K = 2 x 22/7 x 49
K = 44 x 7
K = 308 m

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K = 2πr
K = 2 x 22/7 x 21
K = 44 x 3
K = 132 m

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K = 2πr
K = 2 x 3,14 x 5
K = 6,28 x 5
K = 31,4 cm

___________________________

K = 2πr
K = 2 x 3,14 x 12
K = 6,28 x 12
K = 75,36 cm

___________________________

K = 2πr
K = 2 x 22/7 x 10,5
K = 44 x 1,5
K = 66 cm

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K = πd
K = 22/7 x 70
K = 22 x 10
K = 220 cm

___________________________

K = πd
K = 22/7 x 2,8
K = 22 x 0,4
K = 8,8 cm

___________________________

K = πd
K = 3,14 x 15
K = 47,1 m

___________________________

K = πd
K = 3,14 x 50
K = 157 m

___________________________

K = πd
K = 3,14 x 24
K = 75,36 cm

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