Question

Me expliquem passo a passo como resolver as seguintes contas:
a) -1/2 + 2/5 . 3/1 =

b) 4 . 1/5 + 2/6 +

c) (3/5 . 1/2 + 2/5 ) : (2/7 . 3/4 + 1/2 ) =

Ficarei grata

Answer 1

a)
= -1/2 + 2/5 . 3/1
= -1/2 + 6/5
= [5.(-1) 2.6]/10
= (-5 + 12)/10
= 7/10

b)
= 4 . 1/5 + 2/6
= 4/5 + 1/3
= (3.4 + 5.1)/15
= (12+5)/15
= 17/15

c)
= (3/5 . 1/2 + 2/5 ) : (2/7 . 3/4 + 1/2 )
= (3/10 + 2/5) : (6/28 + 1/2)
=[(1.3+ 2.2)/10] : (3/14 + 1/2)
= 7/10 : [(1.3 + 7.1)]/14
= 7/10 : 10/14
= 7/10 : 5/7
= 7/10 . 7/5
= 49/50