SOLUTION: I have a problem: In the beginning there were 40. Their number increased exponentially. Five years later there were 140. How many would there be in 5 more years (a total of 10 year

Question 1103352: I have a problem: In the beginning there were 40. Their number increased exponentially. Five years later there were 140. How many would there be in 5 more years (a total of 10 years)?
My answer was 487.2, but I don't think I got it right. Can you help me solve this?
Answer by greenestamps(13203) (Show Source): You can put this solution on YOUR website!

Your answer is not right....

It would be a big help if you showed us HOW you got your answer; then we could show you what you did wrong. Learning from your mistakes is a good way to learn.

Since we don't know how you got your answer, all we can do is show you how to get the answer, and hope you learn from that.

In this problem, we are given the population in the beginning and after 5 years, and we are to find the population after another 5 years.

We could use logarithms and/or exponential functions to solve the problem; however, since the time intervals are the same, finding the answer is much simple than all that.

The growth factor over 5 years was 140/40 = 3.5; the growth factor over the next 5 years will again be 3.5.

So 140*3.5 = 490 is your answer.

If you need help setting up and solving the problem using an exponential function, re-post the question specifically asking for that kind of help.
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