Giải thích các bước giải:
`c,`
`7 3/11 - ( 1 5/7 + 2 3/11 )`
`= 7 + 3/11 - ( 1 + 5/7 + 2 + 3/11 )`
`= 7 + 3/11 - 1 - 5/7 - 2 - 3/11`
`= ( 7 - 1 - 2 ) + ( 3/11 - 3/11 ) - 5/7`
`= 4 - 5/7 = (4.7-5)/7 = 23/7`
`d`
`6/7 + 5/8 . 20% - 3/16 . (-2)^2`
`= 6/7 + 5/8 . 1/5 - 3/16 . 4`
`= 6/7 + 1/8 - 3/4`
`= (6.8+1.7-3.14)/56 = 13/56`