Show:
addition
subtraction
rounding to the nearest 10
rounding to the nearest 100
next 3 numbers
100

17 + 10

27

100

35 - 5

30

100

77

80

100

342

300

100

2, 4, 6, 8

10, 12, 14

200

28 + 5

33

200

29 - 19 

10

200

159

160

200

158

200

200

5, 10, 15

20, 25, 30

300

37 + 11

48

300

77 - 6

71

300

696

700

300

913

900

300

3, 6, 9

12, 15, 18

400

83 + 13

96

400

82 - 20

62

400

24

20

400

358

400

400

10, 20, 30

40, 50, 60

500

57 + 20

77

500

93 - 33

60

500

97

100

500

284

300

500

4, 8, 12

16, 20, 24