4

Set 12: Exponential Functions (Intermediate)

Explanation

Answer: A

Which investment grows faster over the long term?

A: $5,000 at 6% compounded annually B: $7,000 at 4% compounded annually

A.

Investment A

✓ Correct
B.

Investment B

C.

They grow at the same rate

D.

Cannot determine

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Compare growth rates over time. 1. Investment A: AA(t)=5000(1.06)tA_A(t) = 5000(1.06)^t. 2. Investment B: AB(t)=7000(1.04)tA_B(t) = 7000(1.04)^t. 3. Long-term: Higher growth rate (6% vs 4%) dominates. 4. Crossover: Eventually, 5000(1.06)t>7000(1.04)t5000(1.06)^t > 7000(1.04)^t as tt increases. 5. Test t=20t=20: - A: 5000(1.06)2016,0365000(1.06)^{20} \approx 16,036 - B: 7000(1.04)2015,3467000(1.04)^{20} \approx 15,346 Strategic Tip: In exponential functions, the base (growth rate) dominates in the long run. Choice B is incorrect because despite higher initial value, lower rate loses. Choice C is incorrect because different rates mean different growth. Choice D is incorrect because we can compare by calculating.

Key Steps:

The correct answer is Investment A

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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