one
ten
100

1+1=

2

100

10+20

30

200

4+5=

9

200

80-40

40

300

8+1=

9

300

40+40

80

400

6-7=

-1

400

30-40

-10

500

3-5=

-2

500

40-80

-40

M
e
n
u