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Question
The population of a town increases at the rate of 50 per thousand. Its population after 2 years will be 22050. Find its present population.
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Solution
Population after two years = P \[\left( 1 + \frac{R}{100} \right)^n \]
\[22, 050 = P \left( 1 + \frac{50}{1000} \right)^2 \]
\[22, 050 = P \left( 1 . 05 \right)^2 \]
\[P = \frac{22, 050}{1 . 1025}\]
\[ = 20, 000\]
Thus, the population two years ago was 20, 000.
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