pakai cara nomor 2 sampai 10

1) D=20cm r=1/2×D=10cm
s=26cm
L.slimut=phi×s×r=3,14×26×10=816,4

2) r=14cm
t=10cm
L.slimut tabung=2×phi×r×t=2×22/7×14×10
=880cm persegi

3) r=3cm
L=4×phi×r×r=4×3,14×3×3=1130,4cm persegi

4) D=14cm r=1/2D=7cm t=24cm
s^2=t^2+r^2
=24^2+7^2=625
[tex]s = \sqrt{625} = 25[/tex]

L.permukaan kerucut=phi×r(s+r)
= 22/7×7(25+7)
=22×32=704cm persegi

5) t=8cm D=14cm r=1/2D=7cm
V=phi×r×r×t=22/7×7×7×8=1232cm kubik

6) t=18cm D=14cm r=1/2D=7
V=1/3×phi×r×t=1/3×22/7×7×18=132cm kubik

7) r=4cm
V=4/3×phi×r×r×r=4/3×22/7×4×4×4
=268,19cm kubik

8) V=1540cm kubik t=10cm
V=phi×r×r×t
1540=3,14×r×r×10
1540=31,4×r×r
r^2=1540 : 31,4=49
[tex]r = \sqrt{49} = 7cm[/tex]

9) V=38.808cm kubik
V=4/3×phi×r×r×r
38808=4/3×r×r×r
r^3=38808:4/3=29,106
[tex]r = \sqrt[3]{29.106} [/tex]
r=3,08cm
L=4×phi×r×r
=4×3,14×3,08×3,08
=119,14cm persegi

10) V=1540cm kubik t=10cm
V=phi×r×r×t
1540=3,14×r×r×10
1540=31,4×r×r
r^2=1540:31,4=49
r=7 (kalo yg dicari jari jarinya)

No.10 yang dicari apanya boosss???