Respostas

2014-03-26T16:29:05-03:00
[3 + 8]-[8+1]= 11 - 9 = 2
ou
[3 + 8] -[8 +1] = 3 + 8 - 8 - 1 = 2  ( cancelando 8 - 8 = 0)


2014-03-26T16:45:42-03:00