A deer population in a forest starts with 100 and increases by 9% each year. Write an exponential function that models the data, there is ten years in this graph

1 answer

To model the deer population with an exponential function, we can use the general formula for exponential growth:

\[ P(t) = P_0 \times (1 + r)^t \]

where:

  • \( P(t) \) is the population at time \( t \),
  • \( P_0 \) is the initial population,
  • \( r \) is the growth rate (as a decimal), and
  • \( t \) is the time in years.

In this case:

  • The initial population \( P_0 = 100 \),
  • The growth rate \( r = 0.09 \) (since 9% expressed as a decimal is 0.09).

Plugging these values into the formula gives:

\[ P(t) = 100 \times (1 + 0.09)^t \]

which simplifies to:

\[ P(t) = 100 \times (1.09)^t \]

Now, to find the population for each year from 0 to 10, we can evaluate \( P(t) \) for \( t = 0, 1, 2, \ldots, 10 \).

For the values:

  • \( P(0) = 100 \times (1.09)^0 = 100 \)
  • \( P(1) = 100 \times (1.09)^1 \approx 109 \)
  • \( P(2) = 100 \times (1.09)^2 \approx 118.81 \)
  • \( P(3) = 100 \times (1.09)^3 \approx 128.50 \)
  • \( P(4) = 100 \times (1.09)^4 \approx 139.22 \)
  • \( P(5) = 100 \times (1.09)^5 \approx 150.15 \)
  • \( P(6) = 100 \times (1.09)^6 \approx 161.23 \)
  • \( P(7) = 100 \times (1.09)^7 \approx 172.59 \)
  • \( P(8) = 100 \times (1.09)^8 \approx 184.16 \)
  • \( P(9) = 100 \times (1.09)^9 \approx 196.01 \)
  • \( P(10) = 100 \times (1.09)^{10} \approx 208.19 \)

Thus, the population after 10 years will be approximately 208 deer.

The exponential function describing the deer population is:

\[ P(t) = 100 \times (1.09)^t \]

for \( t = 0, 1, 2, ..., 10 \).