`5`

`a) 1/6 +1/3= 1/6 + 2/6 = (1+2)/6 = 3/6 = 1/2`

`b) -5/12 + 2/-3 = -5/12 - 2/3 = -5/12 - 8/12 = -13/12`

`c) -5/8 - 7/-12 = -5/8 + 7/12 = -1/24`

`d) 15/48 - (-5/12) = 15/48 + 5/12 = 15/48 + 20/48 = 35/48 `

`e) 1/4 + (-4/5) -3/10`

`= 1/4 - 4/5 -3/10`

`= 1/5 - 3/10`

`= 2/10 - 3/10 = -1/10`

`f) -1/5 + 11/9 + 1/5`

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

`= 0  + 11/9 = 11/9`

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

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

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

`= 1 - 1`

`= 0`

`h) 7/5 - 13/9 + (-12/5) + 4/9`

`= (7/5 - 12/5) - (13/9 -4/9)`

`= -1 - 1`

`=`` -2`