Notam:
a= suma pe care o are Dan
b = suma pe care o are Cristian
a+b = 120 lei
a+b:4 = b-b:4 |×4
4×a+b = 4×b-b
3×b-b = 4×a
2×b = 4×a | : 2
b = 2×a
a |____|
b |____|____|
Avem 2 segmente egale = 120
120 : 3 = 40 (un segment)
a = 40
b = 2×40 = 80
Verificare:
40+80 = 120
40+80:4 = 80-80:4
40+20 = 80-20
60=60
Dan a avut 40 lei
Cristian a avut 80 lei