`a) 3/7 + (-5/2) + (-3/5)`
`= 3/7 - 5/2 - 3/5`
`=30/70 - 175/70 - 42/70`
`= -187/70`
``
`b) (-4/3) + (-2/5) + (-3/2)`
`= -4/3 - 2/5 - 3/2`
`=-40/30 - 12/30 - 45/30`
`= -97/30`
``
`c) 4/5 - (-2/7) - 7/10`
`= 4/5 + 2/7 - 7/10`
`= 56/70 + 20/70 - 49/70`
`= 27/70`
``
`d) 2/3 - [ (-7/4) - ( 1/2 + 3/8)]`
`= 2/3 - [ (-7/4) - ( 4/8 + 3/8)]`
`= 2/3 - [ (-7/4) - 7/8]`
`=2/3 - [ (-14/8) - 7/8]`
`= 2/3 - (-21/8)`
`= 79/24`