Reply #122: we need a nat'l requirement for knowing how to calculate exponentials [View All]

[0rganism]

The exponential function is probably far more important to our overall welfare than the quadratic equation, but it's lumped into precalculus so a lot of high school grads will never see how it works - not in high school, anyway.

If you have a credit card with a 25% APR, how long does it take a $10000 debt to become a $20000 debt? How long would it take to pay it off at a rate of $100/month? (hehe)

If your city counselman expressed a desire for 5% annual population growth and his wish came true, how many years would it take for your hometown to have as many people as LA does today? (LA residents excluded, of course)

These kinds of questions are both relevant and answerable, you can get good approximations without a computer, but you have to know where to start. And as a result, a lot of folks won't hesitate to spend big money on a high-interest credit card or blink an eye when they hear a local political goon suggesting something as ludicrous in the long term as 5% annual growth.

Of course, it's much easier to set up the parameters in your mind if you've got a background in algebra...