Răspuns :
Fie x nr kilogramelor de grâu
x - 20/100•x = 650
x - x/5 = 650
5x-x=3250
4x=3250
x=3250/4
x=812,5 kg
x - 20/100•x = 650
x - x/5 = 650
5x-x=3250
4x=3250
x=3250/4
x=812,5 kg
100 kg grau ............. 80 kg faina
x kg grau ............650 kg faina
x = 650*100/80 = 812.5 kg grau
x kg grau ............650 kg faina
x = 650*100/80 = 812.5 kg grau