`-2 2/3+5 1/3:3/8+2 2/3-1`
`=-8/3+16/3xx8/3+8/3-1`
`=-8/3+128/9+5/3`
`=119/9`
`2/7+5/7xx1/5+4/5-1`
`=2/7+1/7-1/5`
`=3/7-1/5`
`=8/35`
`3/5:(-3/4-1)-3/5:(-1/4-1/2)`
`=3/5:(-7/4)-3/5:(-3/4)`
`=3/5xx(-4/7)-3/5xx(-4/3)`
`=-12/35+12/15`
`=240/525`
`=16/35`