Answer to January 26, 2004 Problem

The U.S. Population Problem

 
On January 1, 2004, the population of the United States was 292,287,454.

The U.S. is recording a birth every 8 seconds, a death every 13 seconds, and adding an immigrant every 25 seconds.
Based on this data, determine how many seconds (to the nearest hundredth of a second) that it takes for the U.S. population to increase by one person.

 

Solution to the Problem:

The answer is 11.35 seconds.

Find the lowest common denominator for 8, 13, and 25 -- the LCD is 2600.
So, in 2600 seconds, there are 325 births, 200 deaths, and 104 immigrants added. This is a net result of 325 - 200 + 104 = 229 persons added to the population every 2600 seconds. Dividing 2600 by 229 yields 1 person added every 11.3537 seconds.

Keith Mealy sent in the following:
Or as Red Skelton once said, "Somewhere in the US, a woman is having a baby every 8 seconds. We have to find her and stop her."

Click here to see a comic strip about population growth:


Correctly solved by:

1. Walt Arrison Philadelphia, Pennsylvania
2. Keith Mealy Cincinnati, Ohio
3.John Funk Ventura, California
4. Akash Patel Columbus, Georgia
5. Bill Funk San Antonio, Texas
6. Richard Johnson La Jolla, California
7. James Alarie University of Michigan -- Flint,
Flint, Michigan
8. Matthew Reames Roanoke, Virginia
9. Dave Smith Toledo, Ohio
10. David & Judy Dixon Bennettsville, South Carolina
11. Shannon Bagshaw Winchester, Virginia
12. Jeffrey Gaither Winchester, Virginia
13. Kristofer Friman Tullängensskolan, Sweden
14. Viktor Bergqvist Tullängsskolan,Sweden
15. Eweymae ----------