Understanding Large Numbers

Date: 01/14/98 at 03:25:24
From: Elizabeth Wynn
Subject: Making large numbers relevant

Dear Dr. Math,

     I have a project for school where I need to make 30 billion 
(U.S.) relevant to everyday life.  Do you have any suggestions?

Date: 01/15/98 at 16:01:36
From: Doctor Daniel
Subject: Re: Making large numbers relevant

Hi there,

Large numbers are a pain that way--it's even more of a pain to deal 
with numbers like the number of atoms in the Earth (roughly 10^40, I 
think) or the universe (10^60?), but even numbers like 30,000,000,000 
can be somwhat hard.  

I often try doing things like this: If it were U.S. Dollars, and I 
divided the amount by all of the people in my town (or state, or 
country, or on Earth), how much would we be able to buy?  So, for 
example, I live in Ithaca, New York, which has roughly 50,000 people 
in it. That would mean every person in the city would get $600,000.  
That's still a lot more than I've ever had; if I use the entire State 
of New York (15 million people); then we each would get $2000.  

Another trick which can work reasonably well is to imagine a 
moderately large number as a fraction of the number of cells in your 
brain. Of course, I've forgotten how many brain cells the average 
person has [maybe that says something about me...], but you could look 
that up in an encyclopedia. Say it was 150 billion. Then 30 billion 
brain cells would be 1/5 of your total brain.  

Another trick I've used before is to figure out how many seconds there 
are in a given amount of time; I believe 30,000,000,000 seconds is 
roughly 1000 years!  

Maybe these will help?  It's a fair question, but one that has no easy 
answer.  Much luck with your project!

-Doctor Daniel,  The Math Forum
 Check out our web site!  http://mathforum.org/dr.math/