2
10 + 30 = 40
1 + 3 = 40
3
15 + 30 = 45
1 + 3 = 45
4
45 + 30 = 15
4 + 3 = 15
5
30 + 10 = 20
3 + 1 = 20
6
100 + 7 = 107
107
7
100 + 30 = 130
130
8
156 + 3 = 159
150 +(6+ 3) = 159
9
156 + 20 = 176
156 +(5+ 2) = 176
100 + (50 +20) = 176
10
156 - 3 = 153
150 +(6+ 3) = 153
11
156 - 20 = 136
156 +(5 - 2) = 136
100 + (50 -20) = 136
12
2 + 2+ 2 +2= 8
3 + 3+ 3 = 9
13
100 - 3 = 97
100 - 5 = 95
14
256 + 2 = 258
200 + (6 +2) = 258
15
256 + 20= 276
200 + (50 +20) = 276
16
2 x 3 = 6
4 x 5 = 20
17
10 + 30 + 7 = 47
1 + 3 = 4
18
10 + 30 + 57 = 97
1 + 3 + 5= 9