9

Set 14: Exponential Functions

Explanation

Answer: A

A city's population grows at 3% per year. If the current population is 50,000, what will it be in 5 years?

A.

About 57,964

✓ Correct
B.

57,500

C.

65,000

D.

53,000

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Use exponential growth formula. 1. Formula: P(t)=P0(1+r)tP(t) = P_0(1 + r)^t where P0=50000P_0 = 50000, r=0.03r = 0.03, t=5t = 5. 2. Calculate: P(5)=50000(1.03)5=50000(1.159274)57,964P(5) = 50000(1.03)^5 = 50000(1.159274) \approx 57,964. 3. Result: Population ≈ 57,964. Strategic Tip: Growth rate of 3% means multiplying by 1.03 each year. Choice B is incorrect because this assumes simple addition (50,000 + 7,500). Choice C is incorrect because this assumes too high a growth rate. Choice D is incorrect because this only accounts for one year of growth.

Key Steps:

The correct answer is About 57,964

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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