Question

Suma de 3600 lei se achita in bacnote de 100 si 500 lei. stiind ca au fost folosite in total 16 bacnote, sa se afle cate au fost de fiecare fel?

Answer 1

x- 100 lei
y=500 lei

x+y=16 => x=16-y
x*100+y*500=3600
100(16-y)+500y=3600
1600-100y+500y=3600
400y=3600-1600
400y=2000
y=2000:400
y=5 bancnote de 500

x=16-5
x=11 bancnote de 100

Verificare
11*100+5*500=
1100+2500=3600