Đáp án:+Giải thích các bước giải:
`a, 4 - 7/5 - 8/3 = 13/5 - 8/3 = -1/15`
`b, -1 + 1/3 - 1/9 - 1/81 = -2/3 - 10/81 = -64/81`
`c, 4/5 - (-2/7) - 7/10 = 4/5 + 2/7 - 10/7 = 38/35 - 10/7 = 27/70`
`d, 3/4 - [ 3/4 - ( 2/3 + 5/6 ) ] = 3/4 - [ 3/4 - 3/2 ] = 3/4 - 3/4 + 3/2 = 3/2`
`e, 3/4 - 0,25 - [ 7/3 + (-9/2) ] - 5/6`
= `1/2 + 13/6 - 5/6`
= `8/3 - 5/6`
= `11/6`
`f, 7 + ( 7/12 - 1/2 + 3 ) - ( 1/12 + 5 )`
= `7 + 7/12 - 1/2 + 3 - 1/12 - 5`
= `( 7 + 3 - 5 ) + ( 7/12 - 1/12 ) - 1/2`
= `5 + 1/2 - 1/2`
= `5`