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Question
The population of a village increases at the rate of 50 per thousand. Its population after 2 years will be 22,050. Find the present population.
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Solution
Rate of increase =
r = `50/1000 xx 100` = 5 %
Vn =22,050 ; V0 = ? ; r = 5 % ; t = 2 years
Vn = V0 `(1 + "r"/100)^"t"`
22050 = V0 `(1 + 5/100)^2`
22, 050 = v. × 1.05 × 1.05
V0 = `22050/11025`
V0 = 20000
The present population is 20,000.
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