Question

efetue as subtração
a) 2/5-1/4
b) 5/8-3/8
c) 1/2-1/4
d) 0,6-0,54
e) 1/4-1/8
f)3,8-4/5
com contas prfv 

Answer 1

2/5 - 1/4=
MMC = 20
( 8 - 5)/20  = 3/20 ****

5/8 - 3/8 =  DENOMINADORES IGUAIS DIMINUI NUMERADOR E CONSERVA DENOMINADOR
( 5 - 3)/8 = 2/8 = 1/4 ****

1/2 - 1/4 =
MMC = 4
( 2 - 1)/4 = 1/4 ****

0,6 - 0.54 = 0.06 ***

1/4 - 1/8
MMC = 8
( 2 - 1)/8  = 1/8 ****

3,8 - 4/5
38/10  - 4/5  =
MMC = 20
( 76 - 16 )/20 = 60/20 = 3/1 ****

Answer 2

2/5 - 1/4 = 8/20 - 5/20 = 3/20

5/8 - 3/8 = 2/8

1/2 - 1/4 = 2/4 - 1/4 = 1/4

0,6 - 0,54 = 0,06

1/4 -1/8 = 2/8 - 1/8 = 1/8

3,8 - 4/5 = 3,8 - 0,8 = 3