giúp mình với a) 3/7-2/3+4/7 b) 4/5-(-2/5)-7/10 c) 1/3- -5/6+3/4 d) 2/3+-3/4+2/6 e) 3/5-5/4-2/3 g) 2/6- -2/3+7/4

`a)`

        `3/7-2/3+4/7`

`=(3/7+4/7)-2/3`

`=1-2/3`

`=1/3`

`b)`

        `4/5-(-2/5)-7/10`

`=4/5+2/5-7/10`

`=6/5-7/10`

`=12/10-7/10`

`=1/2`

`c)`

        `1/3- (-5)/6+3/4`

`=1/3+5/6+3/4`

`=4/12+10/12+9/12`

`=23/12`

`d)`

        `2/3+(-3)/4+2/6`

`=2/3-3/4+2/6`

`=8/12-9/12+4/12`

`=1/4`

`e)`

        `3/5-5/4-2/3`

`=36/60-75/60-40/60`

`=-79/60`

`g)`

        `2/6- (-2)/3+7/4`

`=1/3+2/3+7/4`

`=1+7/4`

`=11/4`

`#` $kiddd$