17
+
20
=
20
+
67
=
4
+
63
=
25
+
3
=
3
+
81
=
64
+
13
=
63
+
5
=
15
+
7
=
75
+
10
=
10
+
7
=
2
+
83
=
7
+
66
=
17
+
14
=
41
+
51
=
85
+
11
=
9
+
3
=
19
+
71
=
40
+
36
=
32
+
1
=
9
+
16
=