SOLUTION: help A certain forest covers an area of 2100km^2. Suppose that each year this area decreases by 6.25%. What will the area be after 8 years? Round to nearest square kilometer.

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Question 1173073: help
A certain forest covers an area of 2100km^2. Suppose that each year this area decreases by 6.25%. What will the area be after 8 years?
Round to nearest square kilometer.

Found 2 solutions by ewatrrr, greenestamps:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 
Hi,
A certain forest covers an area of 2100km^2.
Suppose that each year this area decreases by 6.25%.
As Your Instructor said:
Take into account what happens at the close of the 1st year...
100%-6.25% = 93.75% ... it is .9375 of its size
What will the area be after 8 years?
A%5B8%5D+=+A%5B0%5D%28.9375%29%5E8+
A%5B8%5D+=+2100%28.9375%29%5E8 = 1253km^2 (rounding to nearest square kilometer)
Wish You the Best in your Studies.

Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


The solution from the other tutor uses the formula for continuous exponential decay; that is not appropriate for the given question.

The area of the forest decreases by 6.25% per year, so the area gets multiplied by 1-0.0625 = .9375 each year. After 8 years, the original 2100 km^2 will be reduced to

2100(0.9375)^8 = 1253 km^2