Answer:
After 10 years the size of the city will be 29802.32239
Explanation:
1st year 3200 x 1.25 = 4000
2nd year 4000 x 1.25= 5000
3rd year 5000 x 1.25 = 6250
4th year 6425 x 1.25 = 7812.5
5th year 7812.5 x 1.25 = 9765.625
6th year 9765.625 x 1.25 = 12207.03125
7th year 12207.03125 x 1.25 = 15258.78906
8th year 15258.78906 x 1.25 = 19073.48633
9th year 19073.48633 x 1.25 = 23841.85791
10th year 23841.85791 x 1.25 = 29802.32239