Show:
single digit addition
single digit subtraction
2 digit addition
2 digit subtraction
3 digit addition or subtraction
100

1+1

2

100

5-5

0

100

10+10

20

100

10-10

0

100

100+200

300

200

1+3

4
200

5-3

2

200

15+15

30

200

50-20

30

200

200-150

50

300

5+5

10

300

6-3

3

300

30+40

70

300

90-30

60

300

300+125

425

400

6+7

13

400

8-2

6

400

70+30

100

400

45-20

25

400
125+225

350

500

9+9

18

500

9-1

8

500

50+90

140

500

95-75

20

500

200-152

48