Adding on the Number Line
Subtracting on the Number Line
10 more
10 less
Half
100

5+3

8

100

9-6

3

100

15

25

100

65

55

100

What number is halfway between 0 and 10?

5

200

4+5

9

200

5-1

4

200

37

47

200

41

31

200

What number is halfway between 0 and 20?

10

300

8+2

10

300

10-7

3

300

69

79

300

78

68

300

What number is halfway between 0 and 100?

50

400

40+20

60

400

80-40

40

400

102

112

400

101

91

400

What number is halfway between 0 and 50?

25

500

30+60

90

500

70-50

20

500

110

120

500

118

108

500

What number is halfway between 0 and 60?

30