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Answers and Explanations

Does the number e have any real physical meaning, or is it just a mathematical convenience?

Yes, the number e does have physical meaning. It occurs naturally in any situation where a quantity increases at a rate proportional to its value, such as a bank account producing interest, or a population increasing as its members reproduce.

Obviously, the quantity will increase more if the increase is based on the total current quantity (including previous increases), than if it is only based on the original quantity (with previous increases not counted). How much more? The number e answers this question.

To put it another way, the number e is related to the how much more money you will earn under compound interest than you would under simple interest.

Therefore, we will address the following topics:

You may select any of the items above, or follow the [Go On] links to see them discussed in order.

This page last updated: September 1, 1997
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