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Question
The population of a city is 24,000. In the next 3 years it will be 27,783. Find the rate of growth of the population.
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Solution
Vn = 27 ,783; V0 = 24,000 ; r = ? ; t = 3 years
`"V"_"n" = "V"_0 (1 + "r"/100)^"n"`
27783 = 24000 `(1 + "r"/100)^3`
`27783/24000 = (1 + "r"/100)^3`
`21^3/20^3 = (1 + "r"/100)^3`
`(1 + "r"/100) = 21/20`
`"r"/100 = 21/20 -1`
`"r"/100 = 1/20`
r = `1/20 xx 100`
r = 5 %
The rate of growth of population is 5 %.
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