Răspuns :
6488 * a : 5 : 4 = 4866
6488 * a : 5 = 4866 * 4
6488 * a : 5 = 19464
6488 * a = 19464 * 5
6488 * a = 97320
a = 97320/6488
a = 15
Proba: 6488 * 15 : 5 : 4=
97320 : 5 : 4=
19464 : 4 = 4866
6488 * a : 5 = 4866 * 4
6488 * a : 5 = 19464
6488 * a = 19464 * 5
6488 * a = 97320
a = 97320/6488
a = 15
Proba: 6488 * 15 : 5 : 4=
97320 : 5 : 4=
19464 : 4 = 4866