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The number of birds in a forest is decreasing by 3% every year. If there are 4,363 birds now, how many birds were there 7 years ago?

User Ampy
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1 Answer

3 votes

Answer:

Explanation:

To solve this problem, we can use the formula for exponential decay:

N(t) = N0 * (1 - r)^t

Where:

N0 = initial number of birds

N(t) = number of birds after time t

r = rate of decrease as a decimal (in this case, 0.03)

t = time in years

We want to find N0, the initial number of birds 7 years ago. Let's plug in the given values and solve for N0:

N(t) = 4,363

r = 0.03

t = 7

4,363 = N0 * (1 - 0.03)^7

4,363 = N0 * 0.744

N0 = 4,363 / 0.744

N0 = 5,861.98

Therefore, there were approximately 5,862 birds in the forest 7 years ago before the 3% yearly decrease.

User Kathiria
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