I currently have 4 wild bunnies running around my yard. They are freaking annoying. Especially because they are doubling in number every month. Assuming this continues how many bunnies will be annoying me in 2 years.

y = 67108864 rabbits

Step-by-step explanation:

The equation for growth is

y = a (b) ^ (t)

where a is the initial amount

b is the growth rate and

t is the time in months

2 years = 24 months

Assuming the population doubles at the end of the 1st month

Substituting in what we know

y = 4 (2) ^ (t)

y = 4 * 2 ^ 24

y = 4*16777216

y = 67108864 rabbits

If they do not double at the end of the first month and wait until the second month, divide this number by 2

y = 4 (2) ^ (t-1)

y = 4 * 2 ^ 23

y = 4*8388608

y = 33554432 rabbits