Răspuns :
|____|
|____|12| 66
|____|____|____|____|
66-12=54
54:6=9 (primul)
9+12=21(al doilea)
9×4=36(al treilea)
|____|12| 66
|____|____|____|____|
66-12=54
54:6=9 (primul)
9+12=21(al doilea)
9×4=36(al treilea)