1. **State the problem:**
We are given the number of cases on 1 August as 2284 and on 31 August as 45464. We need to find the daily rate of increase $r$ (expressed as a decimal) assuming exponential growth over 30 days.
2. **Formula used:**
The general formula for exponential growth is:
$$ N = N_0 (1 + r)^t $$
where:
- $N$ is the final number of cases,
- $N_0$ is the initial number of cases,
- $r$ is the daily rate of increase,
- $t$ is the number of days.
3. **Apply the formula:**
Given:
$$ N_0 = 2284, \quad N = 45464, \quad t = 30 $$
Substitute into the formula:
$$ 45464 = 2284 (1 + r)^{30} $$
4. **Solve for $r$:**
Divide both sides by 2284:
$$ \frac{45464}{2284} = (1 + r)^{30} $$
Calculate the left side:
$$ 19.9 \approx (1 + r)^{30} $$
Take the 30th root of both sides:
$$ 1 + r = 19.9^{\frac{1}{30}} $$
Calculate:
$$ 1 + r \approx e^{\frac{\ln(19.9)}{30}} $$
$$ \ln(19.9) \approx 2.99 $$
$$ 1 + r \approx e^{\frac{2.99}{30}} = e^{0.0997} \approx 1.1048 $$
Therefore:
$$ r = 1.1048 - 1 = 0.1048 $$
5. **Interpretation:**
The daily rate of increase from 1 August to 31 August is approximately 10.48%.
6. **Compare with previous rate:**
Previously, the daily increase was 15%. Now it is about 10.48%, which is lower.
7. **Conclusion:**
The preventative measures have had a positive effect as the daily infection rate decreased from 15% to approximately 10.48%. This shows the spread of the virus slowed down.
**Final answer:**
The estimated daily rate of increase from 1 August to 31 August is approximately 10.48%. The preventative measures have positively reduced the infection rate.
Daily Infection Rate
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