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29)L permukaan=2×(p×l+p×t+l×t)
=2×(12×16+12×18+16×18)
=2×(192+216+288)
=2×696
=1.392 cm2(A)

30)V 1=s×s×s
=16×16×16
=4096 cm3

V 2=p×l×t
p=32+16=48 cm
l=16 cm
t=18 cm
=48×16×18
=13.824 cm2

V gab=13.824+4096
=17.920 cm3(D)

29. Rumus permukaan balok : 2 (pl + pt + lt)
                                            = 2 × (12×16)+(12×18)+(16×18)
                                            = 2 × (192 + 216 + 288)
                                            = 2 × (696)
                                            = 1.392 cm²   (A)

30. -Rumus volume kubus : s³
                                       = 16³
                                       = 4.096 cm³

      - Rumus volume balok : p.l.t
                                       = (32+16) × 16 × 18
                                       = 48 × 16 × 18
                                       = 13.824 cm³

  - Volume bangun tsb : Volume kubus + Volume balok
                                   = 4.096 + 13.824
                                   = 17.920 cm³   (D)


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