Question

trei copiii au impreuna 200 de timbre.primul are cu 35 de timbre mai mult decat al doilea,iar al trilea are cu 45 timbre mai mult decat al doilea.calculati cate timbre are fiecare

Answer 1

c1+c2+c3=200. c1=c2+35. c3=c2+45. c2+35+c2+c2+45=200. 3c2+35=200-45. 3c2+35=155. 3c2=155-35. 3 c2=120. c2=120:3. c2=40. c1=40+35. c1=75. c3=40+45. c3=85. proba. 75+40+85=200