Amdahl$$s Law is basically the Law of Diminishing Returns, which applies to investments as well as computer architecture. Here is an example that helps explain the law$$Your brother has joined a start$-$up and is trying to convince you to invest some of your savings, since, he claims, $$it$$s a sure thing!$$

You decide to invest $10\%$ of your savings. What must be the return on your investment in the start$-$up to double your overall wealth, assuming the start$-$up was your only investment?