Show:
1 Digit subtraction
2 digit subtraction
hard 2 digit subtraction
100

10-2

8

100

20-10

10

100

24-13

11

200

8-3

5

200

25-3

22

200

34-15

19

300

7-3

4

300

38-6

32

300

26-17

9

400

4-3

1

400

47-10

37

400

45-26

19

500

9-5

4

500

56-10

46

500

52-26

26