Explicație pas cu pas:
x= total
bicicleta = x/3
chitara = (x - x/3)/3
tableta = 2(x - x/3)/3 = 400
2 (x-x/3)/3 = 1200/3
2 ( 3x/3 - x/3) = 1200
2 (2x/3) = 1200
4x/3 = 1200
4x = 1200 × 3 = 3600
x = 3600/4 = 900
total = x = 900
bicicleta = x/ 3 = 300
rest 900-300 = 600
chitara = rest/ 3 = 600/3 = 200
tableta = 2/3 × rest = 2 × 600 / 3 = 1200/ 3 = 400 (asta e verificarea)