Show:
Addition to 10
Addition to 20
Doubles
Adding 50
Adding 100
100

1+2

3

100

5+6

11

100

3+3

6
100

4+5

9

100

13+5

18

200

4+2

6
200

7+8

15

200

5+5

10

200

11+5

16

200

21+7

28

300

5+3

8

300

11+4

15

300

7+7

14

300

34 + 8

42

300

45+7

52

400

3+6

9

400

15+4

19

400

9+9

18

400

47+5

52

400

68 + 7

75

500

8+2

10

500

13+7

20

500

13+13

26

500

42+7

49

500

89+8

97