Over a period of time, if we know the population at certain time, and the rate of change of the population, we can express the function describing such population by means of these two parameters
Then:
P(t) = P₀ + 4*t
In our case
P(t) = 27000 - 4*t
Sign minus is for decreasing population t is in months, 4 is the rate of change and finally 27000 was population the first time Talulah counted the population
D. 3 to 5
This is because if you simplify the ratio by dividing each number in the ratio by 4, therefore for every group of 5 birds 3 of them are parrots
