`d) 12/5 + 11/4 - (2/5 - 15/23) + (15/12 - 8/23)`

`= 12/5 + 11/4 - 2/5 + 15/23 + 15/12 - 8/23`

`= (12/5 - 2/5) + (15/23 - 8/23) + (11/4 + 15/12)`

`= 2 + 7/23 + (33/12 + 15/12)`

`= 2 + 7/23 + 4`

`= 6 + 7/23`

`= 145/23.`

`e) 2/7 + 2/27 : (-4/9)`

`= 2/7 + 2/27 . (-9)/4`

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

`= 6/21 + (-7)/21`

`= -1/21.`

`f) 3/10 . (-5/6) - 1/8`

`= -1/2 - 1/8`

`= -4/8 - 1/8`

`= -5/8.`

`g) -5/7 . 3/13 - 5/7 . 10/13 + 1 5/7`

`= -5/7 . (3/13 - 10/13) + 12/7`

`= -5/7 . (-1) + 12/7`

`= 5/7 + 12/7`

`= 17/7.`

`h) (-1/2)^2 : 1/4 - 2 . (-1/2)^2`

`= 1/4 . 4 - 2 . 1/4`

`= 1/4 . (4 - 2)`

`= 1/4 . 2 `

`= 1/2.`

$#ptjuoy$