Answer:
After the fifth year, the area will be 2,608.28 square km.
Explanation:
Given,
The area is = 3,800 square km. (or, km^2)
Decreasing rate = 7.25% per year.
After 1st year, the area will be decreased to
= 3,800 - (3,800 x 7.25%)
= 3,800 - 275.5
= 3,524.5 square km.
After 2nd year,
3,524.5 - (3,524.5 x 7.25%) = 3,524.5 - 255.52625 = 3,268.97375 sq. km
After 3rd year,
3,268.97375 - (3,268.97375 x 7.25%) = 3,268.97375 - 237.00 = 3,031.97375 sq. km.
After 4th year,
3,031.97375 - (3,031.97375 x 7.25%) = 3,031.97375 - 219.818 = 2,812.15575 sq. km.
After 5th year,
2,812.15575 - (2,812.15575 x 7.25%) = 2,812.15575 - 203.88 = 2,608.27575 sq. km.
Therefore, after the fifth year, the area will be 2,608.28 square km.
If we do a complex method,
The formula will be,
Total area x (1 - decreasing rate)^ year
= 3,800 x (1 - 0.0725)^5 = 2,608.28 square km.