Răspuns :
S-suma din cont
S*1/4 = S/4 - suma cheltuita pe blana
S*1/2 = S/2 - suma cheltuita pe parfumuri
S-S/4-S/2=(4S-S-2S)/4=S/4 - suma ramasa dupa cumparare parfumuri si blana
S/4*1/3= S/12 - suma cheltuita pe bijuterii
S-S/4-S/2-S/12 = 120
(12S-3S-6S-S)/12 = 120
2S/12 = 120
S = 720 dolari
x- suma initiala
a, b, c - noile resturi
x-x/4=a
a-a/2=b
b-b/3=c
c=120
b-b/3=120 amplif cu 3
3b-b=360
2b=360
b=180
a-a/2=180 amplif cu 2
2a-a=360
a=360
x-x/4=360. amplif cu 4
4x-x=1440
3x=1440
x=480
a, b, c - noile resturi
x-x/4=a
a-a/2=b
b-b/3=c
c=120
b-b/3=120 amplif cu 3
3b-b=360
2b=360
b=180
a-a/2=180 amplif cu 2
2a-a=360
a=360
x-x/4=360. amplif cu 4
4x-x=1440
3x=1440
x=480