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1. |
Business An analyst estimates that the computers his company just bought will depreciate at a rate of 25% per year. At this rate, approximately how long will it take a computer to depreciate to 30% of its original value? |
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A. |
4 years |
B. |
10 years |
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C. |
5 years |
D. |
3 years |
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Hint |
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2. |
Radioactivity The half-life of uranium-232 is 72 years. Find the approximate value of k in the formula y = nekt for uranium-232. Assume t is in years. |
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A. |
-0.0024 |
B. |
-0.0048 |
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C. |
-0.0096 |
D. |
0.0012 |
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Hint |
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3. |
Two cities have insect problems. The insects in City A increase exponentially according to the equation y = 120,000e0.04t. The insects in City B increase exponentially according to the equation y = 90,000e0.08t. In 15 years, which city will have more insects, and by approximately how much? |
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A. |
City A, by about 30,000 |
B. |
City A, by about 80,000 |
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C. |
City B, by about 30,000 |
D. |
City B, by about 80,000 |
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Hint |
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4. |
Two cities have insect problems. The insects in City A increase exponentially according to the equation y = 120,000e0.04t. The insects in City B increase exponentially according to the equation y = 90,000e0.08t. When will the cities have an equal amount of insects? |
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A. |
at t = 7.89 years |
B. |
at t = 34.66 years |
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C. |
at t = 7.19 years |
D. |
at t = 3 years |
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Hint |
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5. |
Suppose a new car loses value at 10% per year for the first 5 years. When should the owner sell it if they want to receive 75% of what they paid for it? |
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A. |
after 2 years |
B. |
after 2.5 years |
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C. |
after 2.73 years |
D. |
after 3 years |
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Hint |
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