「七除八扣 / 七除八拆」

(pos:語句)
<explanation>
yue:將個數字扣除其他項目之後，最後嘅數字，通常呢個數字好細；字面解即係打完七折之後再打八折
eng:not much left after deductions; literally, 20% off after 30% off (i.e. 44% off)
<eg>
yue:又要交税，又要同佢對分，七除八扣之後，我哋賺唔到幾多錢。 (jau6 jiu3 gaau1 seoi3, jau6 jiu3 tung4 keoi5 deoi3 fan1, cat1 ceoi4 baat3 kau3 zi1 hau6, ngo5 dei6 zaan6 m4 dou2 gei2 do1 cin2.)
eng:We have to pay taxes on the profits and only after that get half the share. After these deductions we actually don't earn much.