By Ryann Entwistle

-Japan-

I predicted the population for Japan in the years 2000, and 2010. I have decided to do airports as my governmental service.

1950 - 83,625,000 people - 110 airports

1960 - 94,096,000 people - 124 airports

1970 - 104,331,000 people - 138 airports

1980 - 116,551,000 people - 154 airports

1990 - 127,526,333 people - 168 airports

2000 - 138,501,666 people - 183 airports

2010 - 149,476,999 people - 197 airports

2020 - 160,452,332 people - 212 airports

How I figured this out

I figured out the populations two different ways. One way was by adding and multiplying and the other was by finding out how much the population grew by each year. First I tried to figure out the problem by using the adding method. I took the 1980 population and subtracted the 1970 population. I then took the 1980 population and added the difference between 1970 and 1980. I just kept adding the difference until I got to the year that I needed, which was 2010. 116,551,000 (1980 pop.) - 104,331,000 (1970 pop.) =12,220,000

To figure out the problem by using the multiplying method I almost did the same thing as I did with the adding method. I took the 1980 population and divided it by the 1970 population. I then took the 1980 population and multiplied it by the number that I got when I divided. I kept multiplying until I got to the year 2010. 116,551,000 (1980 pop.) divided by 104,331,000 (1970 pop.) =1.11712722

To figure out the last way I took the population growths for 1950-1960, 1960-1970, and 1970-1980. I found the average for all of those. That was the growth for ten years. I then took the 1980 population and added the average to it. Then I kept adding the average until I got to the year 2000 and 2010. 10,471,000 (1950-1960) +10,235,000 (1960-1970) +12,220,000 (1970-1980) = 32,926,000 32,926,000 divided by 3=10,975,333 (pop. growth in ten years)

I thought that the population where I averaged was the most realistic. So I used those numbers to figure out the airports. To figure out the airports I took the 1994 population and divided it by the number of airports in 1994. I did that to figure out the number of airports per person. Then I took the population that I was trying to figure out the number of airports for and divided it by the number of airports per person. That equaled the number of airports in that certain year. 125,106,937 (pop. in 1994) divided by 165 (# of airports in 1994) = 758,224

Question

I wanted to know if my predictions were very close or not. I guess I won't know until the year 2000, 2010, or 2020. I probably won't remember this project by then though.

Disclaimer

My numbers might be wrong because a lot of my number are rounded instead of putting the decimal. The numbers might be more close if I would have used the decimals, but of course you couldnÍt have a fraction of a person, could you. Also, there could be a major disease or something like that and that would totally make my numbers far off.