`a) ( 6 1/8 - 2 3/4 + 50% ) : 0,3`

`= ( 49/8 - 11/4 + 1/2 ) : 3/10`

`= 49/8 - 22/8 + 4/8 ) : 3/10`

`= 31/8 : 3/10`

`= 31/8 xx 10/3`

`= 155/12`

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`b) 75% - ( 5/2 + 5/3 ) + (- 1)/8`

`= 3/4 - ( 15/6 + 10/6 ) + (- 1)/8`

`= 3/4 - 25/6 + (- 1)/8`

`= 18/24 - 100/24 + (- 3)/24`

`= - 85/24`

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`c) 1,2 xx 25/12 - ( 1/2 + 1/3 ) : (- 5)/6`

 `= 6/5 xx 25/12 - ( 3/6 + 2/6 ) : (- 5)/6`

`= 6/5 xx 25/12 - 5/6 : (- 5)/6`

`= 5/2 - 5/6 xx (- 6)/5`

`= 5/2 + 1`

`= 5/2 + 2/2`

`= 7/2`

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`d) 2/7 - 6/7 : 3 - 3 : 2/3`

`= 2/7 - 6/7 xx 1/3 - 3 xx 3/2`

`= 2/7 - 2/7 - 9/2`

`= 0 - 9/2`

`= - 9/2`

`=>` Áp dụng công thức:

`-` Làm trong ngoặc trước sau đó đến nhân chia cộng trừ:

 `( ) -> [ ] -> { } -> xx -> : -> + -> -`

`-` Làm từ trái sang phải

$# 𝓖𝓻𝓮𝓮𝓷$

`#Chank`

Bài `4:`

`a) (6  1/8 - 2  3/4 + 50%) : 0,3`

`= (49/8 - 11/4 + 1/2): 3/10`

`= (49/8 - 22/8 + 4/8) : 3/10`

`= 31/8. 10/3`

`= 310/24`

`= 155/12`

`b) 75% - (5/2 + 5/3) + (-1)/8`

`= 3/4 - (15/6 + 10/6) + (-1)/8`

`= 3/4 - 25/6 + (-1)/8`

`= 18/24 - 100/24 + (-3)/24`

`= (-85)/24`

`c) 1,2. 25/12 - (1/2 + 1/3) : (-5)/6`

`= 6/5. 25/12 - (3/6 + 2/6) : (-5)/6`

`= 5/2 - 5/6. 6/(-5)`

`= 5/2 - (-1)`

`= 5/2 + 1`

`= 5/2 + 2/2`

`= 7/2`

`d) 2/7 - 6/7 : 3 - 3 : 2/3`

`= 2/7 - 6/7. 1/3 - 3. 3/2`

`= 2/7 - 2/7 - 9/2`

`= 0 - 9/2`

`= -9/2`