Question

Doi frati au impreuna 1 000 de surprize.Daca primul ar da 100 de surprize,iar al doilea si-ar dubla numarul celor avute,amandoi ar avea acelas numar de surprize.Cate surprize are fiecare?

Answer 1

a+b=1000
a-100=x => a=x+100
b+b=x=>2b=x =>b=x/2

x+100+x/2=1000
2x+200+x=2000
3x=2000-200
3x=1800
x=1800:3
x=600

a=600+100
a=700

b=600/2
b=300