Răspuns :
mai intai facem transformarile din m in cm si o sa avem L-400 cm H 210 cm si G=30 cm
400/20=20 de caramizi in lungime
210/7=30 de caramizi in inaltime
20x30=600 de caramizi folosim intr-un zid de 400 cm lungime/210 cm inaltime /10 cm grosime
600x3=1800 de caramizi folosim intr-un zid de 400 cm lungime/210 cm inaltime/30 cm grosime
400/20=20 de caramizi in lungime
210/7=30 de caramizi in inaltime
20x30=600 de caramizi folosim intr-un zid de 400 cm lungime/210 cm inaltime /10 cm grosime
600x3=1800 de caramizi folosim intr-un zid de 400 cm lungime/210 cm inaltime/30 cm grosime