Đáp án + Giải thích các bước giải:
`a) 3/8 - (3/4 - 1/2)`
`= 3/8 - (3/4 + (-2)/4)`
`= 3/8 - 1/4`
`= 3/8 + (-2)/8`
`= 1/8`
`b) (-2)/3 + 3/4 - 1/2 + 1/6`
`= (-8)/12 + 9/12 + (-6)/12 + 2/12`
`= 1/12 + (-6)/12 + 2/12`
`= (-5)/12 + 2/12`
`= (-3)/12 = (-1)/4`
`c) 1/10 - (-1)/12 + 1/15`
`= 6/60 + 5/60 + 4/60`
`= 11/60 + 4/60`
`= 15/60 = 1/4`
`d) 27/23 - (-5)/21 - 4/23 + 16/21 + 1/2`
`= (27/23 + (-4)/23) + (5/21 + 16/21) + 1/2`
`= 1 + 1 + 1/2`
`= 2 + 1/2`
`= 4/2 + 1/2`
`= 5/2`
`e) 17/18 . 24/25 . 10/51`
`= (17/18 . 10/51) . 24/25`
`= 5/27 . 24/25`
`= 8/45`
`f) 8/9 + 1/9 . 2/9 + 1/9 . 7/9`
`= 8/9 + 1/9 . (2/9 + 7/9)`
`= 8/9 + 1/9 . 1`
`= 8/9 + 1/9`
`= 9/9 = 1`
`g) 1/2 . (-3)/4 . (-5)/8 . (-8)/9`
`= (1/2. (-3)/4) . ((-5)/8 . (-8)/9)`
`= (-3)/8 . 5/9`
`= (-5)/24`
`h) 6/5 + 1/6 : (-3)`
`= 6/5 + 1/6. (-1)/3`
`= 6/5 + (-1)/18`
`= 108/90 + (-5)/90`
`= 103/90`
`i) 7/8 : 5/4 . (-10)/7`
`= 7/8 . 4/5 . (-10)/7`
`= 7/10 . (-10)/7`
`= -1`
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