Răspuns :
3888-666 = 3222
3222+3245 = 6467
6467-1221 = 5246
La 5246!
3222+3245 = 6467
6467-1221 = 5246
La 5246!
Fie x numărul necunoscut
x+1221-3245+666=3888
x+1221-3245=3888-666
x+1221-3245=3222
x+1221=3222+3245
x+1221=6467
x=6467-1221
x=5246
x+1221-3245+666=3888
x+1221-3245=3888-666
x+1221-3245=3222
x+1221=3222+3245
x+1221=6467
x=6467-1221
x=5246