Question

Ana si Diana are 90 lei.Ana si Radu are 79 lei.Diana di Radu are 97 lei.cat are fiecare?

Answer 1

fie a=suma anei, d=suma dianei si r=suma lui radu
a+d=90
a+r=79
d+r=97
2(a+d+r)=266
a+d+r=133
a+d=90=>r=43
d+r=97=>d=54
a+d=90=>a=36