Engineering Board Exam Reviewer · Applications: Growth and Decay · medium
A population grows at a rate proportional to its size. If it doubles in 4 years, in how many years will it triple?
- 6 years
- 4.39 years
- 6.34 years
- 8 years
Answer
C. 6.34 years
Solution
P=P0ekt. Doubling in 4 years: e4k=2 k= 2/4. Tripling: ekt=3 t= 3/k=4 3/ 2 6.34 years.
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