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put this solution on YOUR website!Biologists want to set up a station to test alligators in the lake for West Nile Virus. Suppose that the costs for such a station are $6,000 for setup costs and $5.00 to administer each test.
a. Write an expression that gives the total cost to test x animals.
Total cost = 6000 + 5x dollars
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b. You can find the average cost per animal by dividing total costs by number of animals. Write the expression that gives the average cost per animal.
Average cost = (6000+5x)/x dollars
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c. Find the average cost per animal for 10 animals. 100 animals. 1,000 animals.
Comment: Let x = 10 ; then x = 100 ; then x = 1000
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d. As the number of animals tested increases, what happens to the average cost to test the animals?
The average cost decreases
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Would the average cost ever fall below $5.00? If so, identify a value that supports your answer. If not, explain how you know.
Solve (6000+5x)/x < 5
6000+5x < 5x
6000 < 0
That is a contradiction, so the average can never be less than $5.
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e. How many animals should be tested for the average cost to be $9.00 per animal?
Solve (6000+5x)/x < 9
6000+5x < 9x
6000 < 4x
x > 1500
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Cheers,
Stan H.