5

Set 13: Exponential Functions (Advanced)

Explanation

Answer: A

$2,000 is invested at 8% interest compounded quarterly. What is the value after 2 years?

Formula: A=P(1+rn)ntA = P(1 + \frac{r}{n})^{nt}

A.

$2,343.32

✓ Correct
B.

$2,320.00

C.

$2,160.00

D.

$2,400.00

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Use the compound interest formula for quarterly compounding. 1. Values: P=2000P = 2000, r=0.08r = 0.08, n=4n = 4 (quarterly), t=2t = 2. 2. Calculate: A=2000(1+0.084)4×2=2000(1.02)8A = 2000(1 + \frac{0.08}{4})^{4 \times 2} = 2000(1.02)^8. 3. Compute: (1.02)81.17166(1.02)^8 \approx 1.17166, so A2343.32A \approx 2343.32. Strategic Tip: Quarterly means n=4n=4, so divide rate by 4 and multiply time by 4. Choice B is incorrect because this assumes annual compounding, not quarterly. Choice C is incorrect because this uses simple interest. Choice D is incorrect because this calculation is incorrect.

Key Steps:

The correct answer is $2,343.32

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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