Question

un elev are o suma de bani prima zi cheltuieste 1pe4ier a doa zi 20% di rest si ii raman 2160

Answer 1

1) x/4  ;   x-x/4 =4x-x/4 =3x/4   suma ramasa
2)20/100*3x/4 =60x/400 =3x/20
3)   2160  lei
x/4+3x/20+2160 =x  ;   numitor 20
5x+3x+43200 =20x
5x+3x-20x = -43200
12x =43200
x =3600 lei suma de bani a i elevului
verif  ;  3600/4 +3*3600/20 +2160 =900+540+2160 =3600 lei