Show:
Sub Within 20
Add Within 20
Add 10's
2 plus 1-Digit
2 plus 2-Digit
100

9-5=

4

100

15+4=

19

100

30+20=

50

100

25+4=

29

100

11+52=

63

200

10-3=

7

200

12+5=

17

200

20+40=

60

200

56+3=

59

200

60+36=

96

300

15-7=

8
300

9+9=

18

300

60+30=

90

300

40+8=

48

300

55+32=

87

400

17-7=

10

400

6+7=

13

400

50+30=

80

400

32+5=

37

400

63=12=

75

500

19-5=

14

500

12+3=

15

500

20+70=

90

500

51+7=

58

500

56=23=

79