Help hélp giúp vói ạ ạ ạ ạ bủm bủm bẹt bẹt (id fifai:2271092368)

`a,-1/5 +11/9 +1/5`

`=(-1/5 +1/5) +11/9`

`= 0+11/9`

`=11/9`

`b,5/3+ (-7)/6 -2/3 +1/6`

`= ( 5/3 -2/3) + (-7/6 +1/6)`

`= 3/3 -6/6`

`=1-1`

`=0`

`c,7/3-13/9+3+4/9`

`=(7/3 +3) + (-13/9+4/9)`

`=16/3 -9/9`

`= 16/3 -1`

`=13/3`

`d,5/13 + (-5)/7 + (-20)/41+8/13+ (-21)/41`

`= (5/13 +8/13) + (-20/41 -21/41) + (-5)/7`

`= 13/13 - 41/41 + (-5)/7`

`=1-1+ (-5)/7`

`=0+ (-5)/7=-5/7`

`e, 1/28 + (-1)/14+3/28+ (-1)/7 + 3/14`

`= (1/28 + 3/28) + (-1/14 +3/14-1/7)`

`= 4/28 + (1/7 -1/7)`

`= 1/7 + 0`

`=1/7`