Respostas

A melhor resposta!
2014-08-26T10:14:45-03:00
1/2 - 2/4 +3/9 -6/18  (tira o mmc que dá 36)
18-18+12-12  = 0/36 = 0
       36

3/5+3/4+3/10 (mmc = 20)
12+15+6     = 33/20
      20

1 5 1
2014-08-26T12:48:31-03:00
E) 0/30
f) 33/20
..................................... . ......