>>10875959>>10875962brainlets. The course is talking about the "time value of money" which is a roundabout way of applying the concept of opportunity cost to money. A discount rate of 10% means that you could be investing your money into something with an average of 10% return in one year (interest rates, stocks, a business opportunity, etc.) If you choose to forgo $100 now for $110 in one year, you have to consider your options for investment because you might be losing out on better investment opportunities now.