Show:
addition
addition
subtraction
subtraction
addition / subtraction
100

12 + 23

35

100

10 + 20

30

100

50-20

30

100

19-12

7

100

54+45

99

200

11 +13

24

200

22+31

53

200

87-24

63

200

14-10

4

200

55-44

11

300

15+32

47

300

50+15

65

300

99-25

74

300

25-11

14

300

79-78

1

400

30+20

50

400

49+46

95

400

97-10

87

400

45-21

24

400

48+45

93

500

79+45

124

500

66+99

165

500

89-74

15

500

87-78

9

500

99+88

187