Jawabanmu

2014-03-26T17:36:49+07:00
P x l x t = 5 : 3 : 2
p = 80 cm  l = ...?
 5  x  X  = 80
10
X  =  80 x 10
                5
X  =  160 cm

l = 3  x  160
    10
  = 48 cm
2014-03-26T18:11:07+07:00
 \frac{p}{l} =  \frac{5}{3} \\ p =  \frac{5}{3}l  \\  \\  \frac{l}{t} =  \frac{3}{2}      \\  t = \frac{2}{3}l
panjang kerangka = 4 ( p x l x t)
80 = 4 ( p + l + t)
20 = p  + l + t
20 =  \frac{5}{3}l+ \frac{2}{3}l+ l
20 = \frac{10} {3}l
l = 6 cm