Adding 10
Subtracting 10
Subtracting tens
100

10 + 5 =

15

100

10 - 10 = 

0

100

70 - 30 =

40

200

10 + 20 =

30

200

30 - 10 =

20

200

40 - 20= ?

Think 20 + ___ = 40

So, 40 - 20 = ____

Think 20 + 20 = 40

So, 40 - 20 = 20

300

66 + 10 =

76

300

53 - 10 =

43

300

One box has 40 magnetic tiles. Another box has the same number of magnetic tiles. How many tiles are there in all?

40 + 40 = 80

80 magnetic tiles

400

72 + 10 =

82

400

69 - 10 =

59

400

62 + 20 =

82

500

 10 +81  =

91

500

84 - 10 =

74

500

37 - 10 =

27

600

88 + 10 =

98

600

97 - 10 =

87

600

You have 26 trading cards and buy 40 more. Your friend has 65 trading cards. Who has more trading cards?

Compare ____  < or > _______ Who has more cards?

26 + 40 = 66

66 > 65

You