la mate.Calculeaza,apoi verifica prin operatie indicata.

•23+36=59
•48+31=79
•26+13=39
39-13=26
•64+25=89
89-64=25
•36+42=78
42+36=78
78-36=42
78-42=36
•72+27=99
27+72=99
99-27=72
99-72=27