Turnover period = Store establishment cost / Monthly operating profit
Recovery period = Store establishment cost / (Monthly operating income - Monthly operating cost)
Two simple formulas, taught my dad for 4 hours, used numerical deduction, strong memorization, and scenario practice, but dad still couldn't fully grasp it.
Only the final scenario practice gave him some feeling. Dad has a period of addiction to short videos without using his brain, but I didn't expect his logic and comprehension abilities to deteriorate so severely, like two different people from his younger days. Fortunately, I discovered it today.
The brain will deteriorate if not used. I really don't want my parents to be out of touch with this era. What they taught me little by little when I was young, I am now turning around to teach them.``