Răspuns:
|__|__|__|__|__|__|__|__|__|__| S
|__|__|__| 30%=3/10 prima zi
|___|___| 20%=2/10 a doua zi
|__|__| 1/4 =25% a treia zi
30%+20%+25%= 75% primele 3 zile 1/4=25%
25%=50 lei ( a patra zi)
25% a treia zi =50 lei 50+50 =100 lei ( a 3+4 -a zi) adica jumatate din suma
100*2=200 lei suma
20%*200= 40 lei a doua zi
prima zi =100-40=60 lei
