Doubles
Base 10 Blocks
Decompose 2 Addends
Adjust Addends
Number Line
100

2+2

4

100

15+21

36

100

21+12

33

100

21+39

60

100

10+15

25

200

4+4

8

200

24+15

39

200

33+24

57

200

43+47

90

200

29+31

60

300

10+10

20

300

45+38

83

300

61+35

96

300

28+39

67


300

47+32

79

400

20+20

40

400

34+29

63

400

57+42

99

400

59+26

85

400

54+43

97

500

40+40

80

500

75+19

94

500

43+35

78

500

27+32

59

500

71+27

98