A species of endangered tigers has a population in 2020 of about 900, and that number is expected to decline by about 4% each year.

Question

A species of endangered tigers has a population in 2020 of about 900, and that number is expected to decline by about 4% each year. If this rate continues, what would we predict the tiger population to be in 2040?

= tiger

Answer 1

We're looking to use the standard form of exponential decay.

P(t) = a(b)^t

a = initial value of 900

t = time

b needs to capture the decay rate r

r = b-1

b = 1 - r = 1 - 0.04 = 0.96

If the initial date is 2020 and the prediction year is 2040, the time passed is 20 years.

You have everything you need to set-up the formula and plug in the years to predict the number of tigers in 2040.