Răspuns:
3c+5b=10,5lei/*2
2c+3b=6,55lei/*3
_____________
6c+10b=21lei
6c+9b=19,65lei
_____________
10biscuiti-9biscuiti=21lei-19,65lei=
1biscuit=1,35lei
___________________________
3ciocolate=5b*1,35lei.....10,50lei
3ciocolate=6,75lei......10,50lei
3ciocolate=10,50lei-6,75lei
3ciocolate=3,75lei
1ciocolata=3,75lei:3ciocolate
1ciocolata=1,25lei
____________________________
10:1,25lei=8lei costă un baton de ciocolată de 10lei.
