Bantu yaaa tolong cepet hehehhe

18)
Dik : r = 5cm, V = 1.100cm³
Dit : t = ...?
Jb:
V tabung = 1.100
πr²t = 1.100
3,14 × 5² × t = 1.100
3,14 × 25 ×t = 1.100
78,5t = 1.100
t = 1.100/78,5
t = 14 cm
Jawaban : C

19)
Dik : d = 12cm, r =6cm, t = 8 cm
Dit : L sisi tabung = ...?
Jwb:
L sisi tabung
= 2πr (r + t)
= 2 × 3,14 × 6 (6+ 8)
= 37,68 (14)
= 527,52
= 528 cm²
Jawaban : A

20)
Dik : d=20cm, r=10cm, t=15cm
Dit : V kerucut = ...?
Jwb :
V Kerucut
= ⅓ πr²t
= ⅓ 3,14 × 10² × 15
= ⅓ × 15 × 314
= 5 × 314
= 1.570 cm³
Jawaban : A

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