Raspunsul:
V=AB*BC*AA
6*BC*3=90
18*BC=90
BC=90:18=5m
________
aria tavan=ab*bc=6*5=30m^2
aria pereti=2*ab*aa + 2*bc*aa
=2*6*3 + 2*5*3
=36+30
=66m^2
aria vopsita=30+66
=96m^2
cantitatea de vopsea necesara=96*200
=19200 g
adica>19,2 kg
cantitatea din 20 de cutii=20*1
=20
20kg»19,2kg =ajung 20 de cutii de vopsea
