Đáp án:
`text{Câu 1}`
`a,`
`A = 13/6 + 5/8 ÷ (-3)/4 - 7/12 × 4`
`-> A = 13/6 + (-5/6) - 7/3`
`-> A = 4/3 - 7/3`
`-> A =-1`
`text{Vậy A= -1}`
`b,`
`B = (7 3/5 - 2 1/3) + (4/3 - 4 3/5)`
`-> B = 7 4/5 - 7/3 + 4/3 - 4 3/5`
`-> B = (7 4/5 - 4 3/5) + (-7/3 + 4/3)`
`-> B = 3 + (-1)`
`-> B = 2`
`text{Vậy B = 2}`
`c,`
`C = 7/5 × 4/9 + 7/5 ÷ 9/16 - 14/10 × 2/9`
`-> C = 7/5 × 4/9 + 7/5 × 16/9 - 14/10 × 2/9`
`-> C = 7/5 × (4/9 + 16/9) - 14/10 × 2/9`
`-> C = 7/5 × 20/9 - 14/10 × 2/9`
`-> C = 28/9 - 14/45`
`-> C = 14/5`
`text{Vậy C =}` `14/5`
`text{Câu 2}`
`a,`
`(x - 1) ÷ 4/3 + 9/16 = (-5)^2/4^2`
`-> (x - 1) ÷ 4/3 + 9/16 = 25/16`
`-> (x - 1) ÷ 4/3 = 25/16 - 9/16`
`-> (x -1)÷4/3=1`
`-> x - 1 = 1 × 4/3`
`-> x - 1 = 4/3`
`-> x = 4/3 + 1`
`-> x = 7/3`
`text{Vậy}` `x = 7/3`
`b,`
`5/2 (x + 2) - 3 1/3 = 1/6`
`-> 5/2 (x + 2) - 10/3 = 1/6`
`-> 5/2 (x + 2) = 1/6 + 10/3`
`-> 5/2 (x + 2) = 7/2`
`-> x + 2 = 7/2 ÷ 5/2`
`-> x + 2 = 7/5`
`-> x = 7/5 - 2`
`-> x = (-3)/5`
`text{Vậy}` `x = (-3)/5`
