Question

Please Help Exponential Decay
See Attachment

Answer 1

Looking at the graph, number of people at
year 0 80,000
year 6 40,000
year 12 20,000

So we can say that the "half-life" is 6 years.
And the formula for this would be:
Present Population = Beginning amount / 2^n
(where 'n' is the number of half-lives or (elapsed time/halflife)

So what is population after 6 years?
Population = 80,000 / 2^(6 yrs / 6yrs)
Population = 80,000 / 2^1
Population = 40,000

Now for something a little tougher:
Population after 7 years?
Population = 80,000 / 2^(7 yrs / 6yrs)
Population = 80,000 / 2^(7 yrs / 6yrs)
Population = 80,000 / 2^(7/6)
Population = 80,000 / 2.2449240966
Population = 35,636

Answer 2

okay, that makes sense. thank you

Answer 3

u r welcome
:-)