Show:
1 digit addition
1digitsubtraction
2digitsaddition
2 digitssubtraction
Even/odd
100

5+2

7

100

5-2

3

100

10+11

21

100

21-10

11

100

32

Even

200

5+4

9

200

9-4

5

200

14+12

26

200

26-12

14

200

41

Odd

300

6+7

13

300
7-6

1

300

18+21

39

300

39-21

18

300

27

Odd

400

9+4

13

400

9-4

5

400

31+42

73

400

73-42

31

400

48

Even

500

9+8

17

500

9-8

1

500

78+21

99

500

99-21

64

500

64

Enen