Respuestas

2013-11-06T22:00:45+01:00
12 + (2-8)= 6

11 - (10 - 6)= 7

4 + (2 - 8)= -2

10 - (11 - 3)= 2

30 - (25 - 5)= 10

3 - (+4)= -1

5 - (-3)= 8

8 - (6 + 4)= -2

13 - (6 - 10)= 17

30 + (10 - 20)= 20