8

Set 7: Exponential Functions (Advanced)

Explanation

Answer: A

An endangered species population triples every 10 years. If there are now 150 individuals, how many will there be in 30 years?

A.

4,050

✓ Correct
B.

1,350

C.

450

D.

13,500

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Apply the tripling pattern. 1. Periods: 3010=3\frac{30}{10} = 3 periods of tripling. 2. Formula: P(t)=150(3)t/10P(t) = 150(3)^{t/10} where t=30t = 30. 3. Calculate: P(30)=150(3)3=150(27)=4,050P(30) = 150(3)^3 = 150(27) = 4,050. Strategic Tip: 3 triplings = multiply by 33=273^3 = 27. Choice B is incorrect because this is after 2 triplings (20 years). Choice C is incorrect because this is after only 1 tripling (10 years). Choice D is incorrect because this would be after 4 triplings.

Key Steps:

The correct answer is 4,050

Why others are wrong:
B: Choice B is incorrect and may result from a calculation error.
C: Choice C is incorrect and may result from a calculation error.
D: Choice D is incorrect and may result from a calculation error.

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