A population of 15 rabbits doubles in size every month. How many rabbits will there be after 7 months?

Write an exponential function for the situation above.
Use your equation to determine how many rabbits there will be after seven months.

1 answer

To model the rabbit population growth, we can use an exponential function. The general formula for exponential growth is given by:

\[ P(t) = P_0 \cdot r^t \]

where:

  • \( P(t) \) is the population at time \( t \),
  • \( P_0 \) is the initial population,
  • \( r \) is the growth factor (how many times the population grows each period),
  • \( t \) is the time in months.

In this case:

  • The initial population \( P_0 = 15 \) (the starting number of rabbits),
  • The population doubles every month, so the growth factor \( r = 2 \) (the population multiplies by 2 each month),
  • We want to find \( P(t) \) for \( t = 7 \) months.

Substituting these values into the formula, we get:

\[ P(t) = 15 \cdot 2^t \]

Now, we can determine the number of rabbits after 7 months by substituting \( t = 7 \) into the equation:

\[ P(7) = 15 \cdot 2^7 \]

Calculating \( 2^7 \):

\[ 2^7 = 128 \]

Now plug this value back into the equation:

\[ P(7) = 15 \cdot 128 \] \[ P(7) = 1920 \]

Therefore, after 7 months, the rabbit population will be \( 1920 \) rabbits.