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The number of trees of a given species per acre is approximated by the modelN = 2500(10^-0.12x), 3<=3<=30where x is the average diameter of the trees (in inches) 4.5 feet above the ground. Use the model to approximate the average diameter (in inches) of the trees in a test plot whenN = 22. (Round your answer to two decimal places.)inNeed Help?Read ItWatch ItSubmit Answer

The number of trees of a given species per acre is approximated by the modelN = 2500(10^-0.12x-example-1
User WiXSL
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We have the next equation:


N=2500\cdot(10^(-0.12x)),3\leq x\leq30

For N = 22, we have:


_{}22=2500\cdot(10^(-0.12x))=(22)/(2500)=10^(-0.12x)

We need to use the concept of the logarithm to find x. Then:


0.0088=(10^(-0.12x)_{})\Rightarrow\log (0.0088)=\log (10^(-0.12x)_{})=-0.12x\cdot\log (10)

Then


\log (0.0088)=-0.12x\cdot1\Rightarrow x=(\log (0.0088))/(-0.12)\Rightarrow x=(-2.0555)/(-0.12)\Rightarrow x=17.1291

Then, the value for x = 17.13 (rounding to two decimal places). This is the solution to the equation.

User Nir Duan
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