5
Answer: ASet 17: Exponential Functions
Explanation
An investment of $15,000 is compounded continuously at 6.5% annual rate. How long until it reaches $30,000?
A.✓ Correct
About 10.7 years
B.
About 15 years
C.
About 8 years
D.
About 12 years
Detailed Explanation
Choice A is correct. Choice A is the correct answer. Solve for using continuous compounding. 1. Formula: . 2. Divide: . 3. Natural log: . 4. Solve: years. Strategic Tip: Doubling time for continuous growth: . Choice B is incorrect because this is too long. Choice C is incorrect because this is too short. Choice D is incorrect because this doesn't match the calculation.
Key Steps:
•
The correct answer is About 10.7 years
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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