We have that if we assume standard exponential growth, the equation of the population will be:[tex]7000*e^{kt}[/tex] if we start counting from the moment that the population was 7000. We are given that 7000* [tex]e^{5k}[/tex]=12000, namely that P(5)=12000 and we need to find [tex]7000e^{(5+5)k}=7000e^{10k}[/tex]. Since e^(10k)=e^(5k)*e^(5k), and since we can solve for e^(5k) from P(5), we have:
e^(5k)=12000/7000 and we can calculate P(10). P(10)=7000[tex] \frac{12000^2}{7000^2} [/tex]= 20571 people.