Question
The population of a town increases by 20% per annum. If
the population after 2 years is 43,200, find its present population.Solution
ATQ,
Let, the present population be ‘x’.
ATQ,
So, the population after 2 years = 1.20 × 1.20 × x = 43200
Or, x = 43200 × (1/1.20) × (1/1.20)
So, x = 30,000
Therefore, present population of the town = x = 30,000
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