Question

Calcule as somas: (com jogo de sinais)

a) (+2/5) + (-1/3) =

b) (-2/3) + (-5/6) =

c) (+3/5) + (-1/3) =

d) (+0,1) + (-1,1) + (0,11) =

2. Efetue as subtrações

a) (+2/5) - (+1/4)

b) (-5/8) + (+3/8)

c) (+1/4) - (-1/2)

d) (-0,54) - (-0,6)

e) (-1/4) - (-1/8)

f) (-4/5) - (+3,8)

Answer 1

1) calcule


a) (+2/5) + (-1/3) =2/5-1/3=> 6-5/15=> 1/15

b)(-2/3) + (-5/6) = -2/3-5/6=> -12-15/18=>
-3/2

c) (+3/5) + (-1/3) =>9-5/15=4/15

d) (+0,1) + (-1,1) + (0,11) = 1/10-11/10=10-110/100= -100/100= -1

2. Efetue as subtrações

a) (+2/5) - (+1/4)=2/5-1/4=8-5/20=3/20

b) (-5/8) + (+3/8)= -40+24/64= -16/64=-1/4

c) (+1/4) - (-1/2)=1/4+1/2=2+4/8=6/8=3/4

d) (-0,54) - (-0,6)=-54/100+6/10=-540-600/1000= -1140/1000= -570/500= - 57/50

e) (-1/4) - (-1/8)= -1/4+ 1/8= -8+4/32=-4/32= -1/8

f) (-4/5) - (+3,8)= -4/5 -38/10= -40/190= -4/19