Show:
Adding fun
Subtraction is fun
More adding
More subtraction
surprise
100

11+1

12

100

9-3

6

100

9+9

18

100

8-2

6

100

7+8

15

200

9+4

13

200

12-9

3

200

13+7

20

200

19-12

7

200

13-9

4

300

32+20

52

300

45-40

5

300

34+21

55

300

44-29

15

300

34+25

59

400

111+111

222

400

123-103

20

400

144+152

296

400

355-211

144

400

210-110

100

500

367+421

788

500

555-222

333

500

351+211

562

500

899-722

177

500

450+550

1000