Răspuns :
7048+5967=13015
Verificare:
7048=13015-5967
7048=7048
5967=13015-5967
5967=5967
4157+3507=7664
Verificare:
4157=7664-3507
4157=4157
3507=7664-4157
3507=3507
Verificare:
7048=13015-5967
7048=7048
5967=13015-5967
5967=5967
4157+3507=7664
Verificare:
4157=7664-3507
4157=4157
3507=7664-4157
3507=3507