Show:
Adding
Subtraction
Numbers in between
numbers after
numbers before
100

5+2 =

7

100

8 - 4 = 

4

100

5_7

6

100

4__

5

100

__8

7

200

6 + 4 = 

10

200

12 - 9 = 

3

200

13___15

14

200

32__

33

200

__12

11

300

52 + 9 = 

61

300

26 - 6 = 

20

300

66 ___ 68

67

300

243____

244

300

___65

64

400

64 + 62 = 

128

400

120 - 45 = 

75

400

124___126

125

400

999____

1000

400

___92

91

500

942 + 653 = 

1595

500

321 - 124 = 

197

500

592___594

593

500

771____

772

500

___778

777