Why Math? pp 77-102

# Powers and Geometric Sequences

• R. D. Driver
Chapter
Part of the Undergraduate Texts in Mathematics book series (UTM)

## Abstract

What do pyramid clubs, hot cups of coffee, gambling outcomes, and inflation rates have in common? Consider the following specific problems.

1. (a)

If each recipient of a certain chain letter dutifully delivers copies of the same letter to just five other persons in 1 week, how many people will be involved in the first 8 weeks?

2. (b)

A cup of coffee in a room where the temperature is 70°F cools from 190°F to 130°F in 6 minutes. How much longer will it take to cool down to 85°F?

3. (c)

Assume you have \$100 for gambling at the roulette wheel, and at each spin of the wheel you bet half the money you then have on red, which is an “even-money” bet. Thus you win or lose the amount of your bet. If you win 10 times and lose 10 times will you end up ahead or behind or even?

4. (d)

If the Consumer Price Index rises 1% per month for 12 months, what is its rise for the entire year?

## Keywords

Interest Rate Roulette Wheel Wage Earner Geometric Series Saving Account
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

## Authors and Affiliations

• R. D. Driver
• 1
1. 1.Department of MathematicsUniversity of Rhode IslandKingstonUSA