Răspuns :
5 zidar...................................................................90 zile
30 zidari...................................................................x
invers proportionale
90×5=30x
x =15
30 zidari...................................................................x
invers proportionale
90×5=30x
x =15
5 zidari...90 zile
30zidari....x zile
5/30=x/90=>x=(90 ori 5) supra 30 = 15
30zidari....x zile
5/30=x/90=>x=(90 ori 5) supra 30 = 15