Question

Daca4 stilouri si3 carti costa 100lei,iar doua stilouri si o carte costa 40lei, calculeaza cat costa un stilou si o carte.

Answer 1

4s+3c=100 lei 2s+c=40 lei 4s+3c-2s-c=60 2s+2c=60 2×(s+c)=60 s+c=60:2 s+c=30