Question

La doua magazine s-au adus in total 108kg de zahar. Cantitatea adusa la primul magazin reprezinta 4/5 din cantitatea dusa la aldoilea magazin. Cite kilograme de zahar s-au adus la fiecare magazin?

Answer 1

a+b=108kg;
a=4/5 ·b;
⇒4/5 ·b+b=108kg
⇒4/5b+b=108kg
⇒4b/5+b=108kg
⇒4b/5+5b/5=108kg
⇒9b/5=108kg
⇒9b=108kg·5
⇒9b=540kg
⇒b=540kg/9
⇒b=60kg;[zahar-al doilea magazin];
⇒a=4/5 ·b
⇒a=4/5·60kg
⇒a=4·12kg⇒a=48kg[zahar-primul magazin];