Jawabanmu

2014-04-15T21:31:41+07:00
Lkub=150 cm2
Lbal = 2x(35+28+20) =2x83=166 cm2

150 : 166 = 75 : 83

Semoga membantu :D
2014-04-15T21:33:04+07:00
Panjang sisi kubus= 5
pjg balok= 7, l= 5, t= 4

Lp kubus : Lp balok
 s^{2} : 2 (pl+pt+lt)
6 ×  5^{2} : 2 ( [7.5]+[7.4]+[5.4])
6 × 25 : 2 × 83
150 : 166
75 : 83