Pow 1 Growth of Rat Populations

Stephen Smith

3/24/2011

Per. 0

POW 1 Growth of Rat Populations

Problem Statement: There are two rats (one male and one female) that are on a ship. They get off on a empty islan to make their own family. If they start having babies on January 1st how many babies would they have in a year depending on these rules.

Six babies every litter and three are girls.

The first litter is made January 1st and there s a new litter every forty days. (By the original mom.)

The younger rats preduce babies every hundred and twenty days. Then every forty days after that.

No rats will die.

Round every month to thirty days.

Process: What I did was wrote out a list skipping every forty days starting at zero. Then i would add the amount of babies boarn on each day. On the next collon i would get the number from the same day add them all up and multiply it by three for the amount of girls. To get the answer I repeated the process untill i was at three-hundred-sixty days (a year). After i got the answer I had to add two to the end because you have to count the original rats. One thing that i tried that did not work was when i tried to wrie out every day in the year andthen add the amount without multiplying at the end. Then when I looked at the answer i knew that there was no way it could be right.

Soulution: To find the answer was easy after I got the process down. What i had to get the number of rats after a year was add all of the numbers up. then after you do that you have to add two more rats because you need to count the original mom and dad rats. After you do all that you come up with 1808 rats at the end of the year.

Evaluation: I thought that this P.O.W was a pretty difficult one because it took a lot of consintration and hard work. When i did this i had to try many diffrent meathods and ways to get the answer that all did not work. Then i finally found the meathod that i think worked to give me the right answer. On a scale from one to ten i think that this was a seven on its difficulty level.

Self-Assessment: I am very confident in my answer being correct because i spent a lot of time working to find the answer. I also worked with some class mates of mine to find the answer. I do believe that my number of rats will be right.