Comment by PaulDavisThe1st

> Most personal finance math is basic arithmetic

Most personal finance is understanding that anyone offering you financial services wants to make money with your money, no matter what they say or how nice they seem.

In some cases, they won't actually reduce the amount you have claim to (like banks holding your money), but will make their money with your money. In other cases, they will take some (hopefully) small percentage of the gain in value of your money, supposedly (and sometimes rightfully) as compensation for the work they claim to have done. In the worst cases, they will gamble with your money in a way that ensures that they never lose, but you may.

Understanding these human factors in real world personal finance comes, in my book, before anything else.