sebuah bola diketahui keliling 66cm hitunglah A. jari jari bola B. luas permukaan bola C. volume bola

a. K = pi.d
66 = 22/7×d
66/22 = d/7
3 = d/7
d = 3×7 = 21 cm
r =21/2 = 10,5 cm

b. LP = 4×pi×r×r
= 4×22/7×10,5×10,5 = (4×10,5)×(22/7×10,5)
= 42 × 33 = 1.386 cm2

c. V=4/3 × pi × r^3
= 4/3 × 22/7 × 10,5 × 10,5 × 10,5
= (4/3 × 10,5) × (22/7 × 10,5) × 10,5
= 14 × 33 × 10,5
= 33 × 147 = 4.851 cm3

A K = 2πr
66 = 2 × 22/7 r
66 = 44/7 r
r = 66 × 7/44
r = 10,5 cm
B L = 4πr² = 4 × 22/7 × 10,5² = 1.386 cm²
C V = 4/3πr³ = 4/3 × 22/7 × 10,5³ = 4.851 cm³