Respostas

2013-08-13T22:35:56-03:00
A) (-4/5) : (8/5) - (2) :(-5/4)
(-4/5) . (5/8) - (2).(-4/5)
(-20/40) - (-8/5)
(-1/2) +(8/5)
mmc
(-5+16)/10
11/10 ou 1,1

b) (-6/30) - (-1/6)
(-1/5)+(1/6)
mmc
(-6+5)/30 = -1/30
2 4 2