Posted by **Erica** on Monday, March 19, 2012 at 5:07pm.

The population of humorville is 8,500 people. In this town, jokes travel fast. In one hour, each person who hears a joke tells three other people who have not heard it, and tells no one else. Last Friday, a visitor from out of town told the police chief a new joke at 10:00a.m. How long did it take for everyone in Humorville to hear it?

- Math -
**bobpursley**, Monday, March 19, 2012 at 5:55pm
after one hour, 3

after two hours, 9+3

after three hours, 27+9+3

so this is a geometric series,

3,9,27, ...3^t

The sum of a geometric series is

St=(1-3^t)/(1-3)=(1-3^t)/-2

or

8500*(-2)=1-3^t

-17000=-3^t

log17000=tlog3

t=8.86, but t is an integer, so t=9 hours.

check my work.

## Answer This Question

## Related Questions

- math - the population of humorville is 8,500 people. in this town, jokes travel ...
- Math - The population of humorville is 8500 people. In this town Jokes travel ...
- algebra - The population of humorville is 8500 people. In this town jokes travel...
- Algebra - Question: Looking below is this answer correct? If you follow the math...
- Language Art help - How does the great radio scare help you gain an ...
- Precal - The number of people in a town of 10,000 who have heard a rumor started...
- math 157 - at the first tri city meeting where 8 people are from twon A 7 people...
- math 157 - at the first tri city meeting where 8 people are from twon A 7 people...
- Math - The number, N, of people who have heard a rumor spread by mass media by ...
- math - At the first tri-city meeting there are 8 people from town A, 7 people ...

More Related Questions