a.-(-31/32 - 7/35) + (-15/32 - 7/15) b.-4/12 - (-3/39 - 0,25) + 0,75 c.-5/7 + (4,25 - 2/7) - (1,25 - 3/2) d.(-0,75) . 18/25 . 4/9 . 50/54 e.(-3/4 + 2/5) : 7/3 + (3/5 +-1/4) : -7/3 giúp mình với

`a, -(-31/32 - 7/35) + (-15/32 - 7/15)`

`= 31/32 +7/35 - 15/32 - 7/35`

`= (31/32 - 15/32 ) + (7/35 - 7/35)`

`=16/32 + 0 `

`=16/32`

`=1/2`

`b, -4/12 - (-3/39 - 0,25) + 0,75`

`= -4/12 + 3/39 + 0,25 + 0,75`

`= (-4/12 + 3/39 ) + (0,25 + 0,75)`

`= -10/39 + 1`

`=29/39`

`c, -5/7 + (4,25 - 2/7) - (1,25 - 3/2)`

`= -5/7 + 4,25 - 2/7 - 1,25 + 3/2`

`= ( - 5/7 - 2/7 ) + ( 4,25 - 1,25 ) + 3/2`

` = -1 + 3 + 3/2`

`=2 + 3/2`

`=7/2`

`d, (-0,75) . 18/25 . 4/9 . 50/54`

`=-3/4. 18/25 . 4/9 . 50/54`

`=(-3/4 . 4/9 ) . (18/25 . 50/54)`

`=-1/3 . 2/3`

`=-2/9`

`e, (-3/4 + 2/5) : 7/3 + (3/5 +-1/4) : -7/3`

`= ( − 3 /4 + 2 /5 + 3 /5 − 1 /4 ) : ( − 7 /3 )`

`= ( − 1 + 1 ) . ( − 3 /7 )`

`= 0 . ( − 3 /7 )`

`= 0 `