Show:
Doubling and Halving
x by 5 and 50
2-digit x 1-digit numbers
Adding 2 2-digit numbers
Compensation method
100

Half of 86

43

100

46 x 5

230

100

60 x 3

180

100

23 + 45

68

100

39 - 17

22

200

Double 34

68

200

34 x 50

1,700

200

90 x 4

360

200

56 + 37

93

200

53 - 21

32

300

Half of 148

74

300

53 x 5

265

300

59 x 2

118

300

83 + 54

137

300

79 - 44

35

400

Double 247

494

400

67 x 50

3,350

400

73 x 6

438

400

66 + 78

144

400

97 - 51

46