Given that population of the city is 280000.
Rate of growth of the population = r = 4.5% = 0.045
We have to find population after 15 years so time
t = 15
We can use growth formula to find the required population which is given by :
![A=P(1+r)^t](https://img.qammunity.org/2019/formulas/mathematics/middle-school/gcbmbtuxr2xadma93whwq2371vu67lp1br.png)
Where P= starting population = 280000
r= rate of growth = 0.45
t= time = 15
now plug these values into above formula.
![A=280000(1+0.45)^(15)](https://img.qammunity.org/2019/formulas/mathematics/high-school/7kmektugypxug3wg9qipbf9p5ddb0olzgk.png)
![A=280000(1.45)^(15)](https://img.qammunity.org/2019/formulas/mathematics/high-school/l200tbleqmrl2ii301pqf95xktuyat1u27.png)
![A=280000(263.34194176)](https://img.qammunity.org/2019/formulas/mathematics/high-school/6efbb1pd2sml6mus5dxc7vev6glegl5wlp.png)
![A=73735743.6928](https://img.qammunity.org/2019/formulas/mathematics/high-school/1vvjk8vwekfz16v120d7ybkaw890ns0mjk.png)
Hence population after 15 years will be approx 73735743.