Răspuns :
ab5 + ab6 = 311
5 + 6 = 11
b + b + 1 = 11
2b = 11 - 1
b = 10 : 2
b = 5
2a + 1 = 3
2a = 3 - 1
a = 1
155 + 156 = 311
5 + 6 = 11
b + b + 1 = 11
2b = 11 - 1
b = 10 : 2
b = 5
2a + 1 = 3
2a = 3 - 1
a = 1
155 + 156 = 311