During one year, the population of a village is increased by 5% and during…
2021
During one year, the population of a village is increased by 5% and during next year, decreased by 5%. If at the end of the second year, the population is 7980, then the population at the beginning of the first year was:
Answer: B. 8000 — Let the initial population be P. After a 5% increase, the population becomes P * 1.05. After a 5% decrease the next year, it becomes (P * 1.05) * 0.95 = P *…
- A.
7980
- B.
8000
- C.
8020
- D.
8200
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Correct answer: B
Let the initial population be P.
After a 5% increase, the population becomes P * 1.05.
After a 5% decrease the next year, it becomes (P * 1.05) * 0.95 = P * 0.9975.
Given the final population is 7980, we set P * 0.9975 = 7980.
Solving for P gives P = 7980 / 0.9975 = 8000.
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