Answer:
Using the formula:
.....[1]
where,
P is the population after t years
is the initial population
r is the rate (in decimal)
As per the statement:
A population of 80,000 toads is expected to shrink at a rate of 9.2% per year.
⇒Initial population(
) = 80,000 toad
and
r = -9.2% = -0.092
We have to find the toad population be in 20 years.
t = 20 years
Substitute the given values in [1], we have;

⇒
Simplify:

Therefore, about 11609 will be the toad population be in 20 years.