x-suma mamei
bluza: x-x/2=(2x-x)/2=x/2
papuci: x/2-x/2·1/4=x/2-x/8=(4x-x)/8=3x/8
tricou:3x/8-3x/8·2/5=3x/8-3x/20=((15x-6x)/40=9x/40
9x/40=63
9x=63·40
x=2520/9
x=280 lei suma cu care mama a plecat la cumparaturi
bluza a costat: 280:2=140 lei
papuci: (280-140):4=35 lei
tricoul: (140-35)x2/5=42
a ramas cu: 280-140-35-42=63 lei