8×9+10 = 72+10 = 82
a+b+c+d = 82
a |____|+10
b |____|+20
c |____|+15
d |____|+5
avem 4 segmente egale +10+20+15+5 = 82
82 - (10+20+15+5) = 82- 50 = 32
32 :4 = 8 ( un segment egal)
a = 8+10 = 18
b = 8+20 = 28
c = 8+15 = 23
d = 8+5 = 13
Verificare:
18+28+23+13 = 82
Cele 4 numere sunt:
18; 28; 23; 13 .