Show:
Add to 20
Subtract to 20
Add to 50
Subtract to 50
Challenge
100

11 + 7

18

100

9 - 2

7

100

23 + 15

38

100

48 - 23

25

100

56 + 38

94

200

8 + 6

14

200

13 - 4

9

200

18 + 21

39

200

50 - 20

30

200

24 + 49

73

300

12 + 3

15

300

15 - 10

5

300

26 + 18

44

300

42 - 18

24

300

82 - 57

25

400

9 + 7

16

400

18 - 12

6

400

34 + 16

50

400

32 - 15

17

400

73 - 46

27

500

17 + 2

19

500

20 - 7

13

500

28 + 19

47

500

50 - 27

23

500

100 - 63

37