1) a |-----|
b |-----|+1| } 13.
13 - 1 = 12 ( 2 parti egale)
12 : 2 = 6 (a)
6 +1 = 7 (b)
Proba : 6 + 7 = 13 .
2) a |-----|
b |-----|+1|
c |-----|+1|+1| } 87.
87 - 3 = 84 ( 3 parti egale)
84 : 3 = 28 (a)
28 +1 = 29 (b)
28 +1+1 = 30 (c)
Proba : 28 +29 + 30 = 87.