Population

The town has 65,000 inhabitants. 40 years ago, there were 157,000. How many people will live in a city in 10 years if the population's average rate is as in previous years?

Correct answer:

x =  52139

Step-by-step explanation:

$$\begin{gathered} n_1=n_2\cdot q^{40} \\ \ln n_1=\ln n_2+40\cdot \ln q \\ \ln q={\displaystyle \frac{\ln 65-\ln 157}{40}} \\ \ln q=-0.0220464633863 \\ q=e^{-0.0220464633863}=0.978194783753 \\ p=-2.18\mathrm{\%} \\ x=65000\cdot q^{10}=65000\cdot 0.978194783753^{10} \\ x=52139 \end{gathered}$$

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