thực hiện phép tính -8 -45 5 -3 1 5 1 3 -1 ----- + ------ ; ----- + ----- ; ---- + ---- + ----- ; ----- + ----- 14 54 12 28 4 8 16 30 5

`-8/14 + (-45)/54`

`= -4/7 + (-5)/6`

`= -24/42 + (-35)/42`

`=  (-59)/42`

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`5/12 + (-3)/28`

`= 35/84 + (-9)/84`

`= 26/84 = 13/42`

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`1/4 + 5/8 + 1/16`

`= 4/16 + 10/16 + 1/16`

`= 15/16`

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`3/30 + (-1)/5`

`= 1/10 + (-2)/10`

`= -1/10`