Question

Daca elevii unei clase se aseaza cate 2 in banca, o banca ramane libera. Daca se aseaza cate 3, raman 4 banci libere. Cati copii si cate banci sunt ?

Answer 1

x-nr de banci

2(x-1) -nr de elevi
3(x-4)

2x-2=3x-12
2x-3x= -12+2
-x= -10

x=10

2(10-1)= 2*9=18 elevi