1. **State the problem:** We have a logistic growth model for the cat population given by
$$P(t) = \frac{84}{1 + 11 e^{-0.07t}}$$
where $t$ is in weeks.
We need to find:
- a) The carrying capacity
- b) The growth rate
- c) The initial population
- d) The population after 5 weeks
2. **Recall the logistic growth model formula:**
$$P(t) = \frac{K}{1 + Ae^{-rt}}$$
where:
- $K$ is the carrying capacity (maximum population)
- $r$ is the growth rate
- $A$ is a constant related to initial conditions
3. **Identify parameters from the given model:**
Comparing,
$$K = 84$$
$$A = 11$$
$$r = 0.07$$
4. **a) Carrying capacity:**
The carrying capacity $K$ is the maximum population the environment can support.
From the formula, $K = 84$.
5. **b) Growth rate:**
The growth rate $r$ is the coefficient in the exponent.
From the formula, $r = 0.07$ per week.
6. **c) Initial population $P(0)$:**
Calculate $P(0)$ by substituting $t=0$:
$$P(0) = \frac{84}{1 + 11 e^{-0.07 \times 0}} = \frac{84}{1 + 11 \times 1} = \frac{84}{12} = 7$$
7. **d) Population after 5 weeks $P(5)$:**
Calculate $P(5)$:
$$P(5) = \frac{84}{1 + 11 e^{-0.07 \times 5}} = \frac{84}{1 + 11 e^{-0.35}}$$
Calculate $e^{-0.35} \approx 0.7047$:
$$P(5) = \frac{84}{1 + 11 \times 0.7047} = \frac{84}{1 + 7.7517} = \frac{84}{8.7517} \approx 9.6$$
**Final answers:**
- a) Carrying capacity $= 84$ cats
- b) Growth rate $= 0.07$ per week
- c) Initial population $= 7$ cats
- d) Population after 5 weeks $\approx 9.6$ cats
Logistic Cat Population D4551F
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.