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Question
Mosquitoes are growing at a rate of 10% a year. If there were 200 mosquitoes in the beginning. Write down the number of mosquitoes after 10 years.
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Solution
Since mosquitoes are growing at a rate of 10% and there were 200 mosquitoes, in the beginning, the number of mosquitoes in successive years form a G.P. with a = 200 and r = `1+10/100=11/10`
Number of mosquitoes after 10 years
= t11
= ar11–1
= `200(11/10)^10`
= 200 (1.1)10
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