4,5m=450cm
3m=300 cm
450*300=135 000 cm patrati
135 000:216=625 cm patrati are o dala
l=rd625
l=25 cm are latura unei dale
20/100+25=20+2500/100=2520/100=25,2 cm latura unei dale
a=25,2*25,2=635,04 cm patratiare o dala
135 000:635,04=212, 5850 dale
212 sau 213 dale