Question

Doi saci contin impreuna 68 kg de cartofi.Daca din primul se iau 13 kg de cartofi si se pun in celalalt ,atunci in fiecare sac ar fi cantitati egale.Cate kg de cartofi contine fiecare sac?

Answer 1

$\rm a+b=68\\a-13=b+13\ |-13\ (Scadem\ 13\ din\ ambele\ relatii)\\a-26=b\longrightarrow a=b+26\\\\b+26+b=68\\2b+26=68\\2b=42\\\boxed{b=21}\\\\a=68-21\\\boxed{a=47}$

Answer 2

a+b=68
a-13=x=>a=13+x
b+13=x=>b=x-13
a+b=68
13+x+x-13=68
2x=68=>x=68:2=>x=34
a=13+34=>a=47
b=34-13=>b=21
Cu placere!