From 2003 onward, the number of daily visitors to a website increased by 200% every two years. So, for example, the number of visitors in 2011 was 200% more than the number of visitors in 2009. In what year was the number of daily visitors 800% more than the number of daily visitors in 2003?

Guest Jun 28, 2017

#2**0 **

If the number of visitors was, say, 100 people in 2003, then in 2005 that number would have gone up to 300 people, which is 200% increase. And that number would have gone up to 900 people in 2007, which is 800% increase.

So, it takes 4 years for daily visitors to grow by 800%.

Another way of looking at it is to find ANNUAL percentage increase as follows:

300 people / 100 people =3-folds increase in 2 years. So the yearly increase would be:

3^1/2 =1.73205 - 1 x 100 = 73.205% average compound annual increase.

900 people =100 x [1 + 73.205%]^N divide both sides by 100

9 = 1.73205^N take the log of both sides.

N =Log(9) / Log(1.73205)

N = 4 Years for the number of visitors to grow by 800%.

Guest Jun 30, 2017

edited by
Guest
Jun 30, 2017