SOLUTION: The atmospheric pressure P in pounds per square inch (psi) is given by P = 14.7 e−0.21 awhere a is the altitude above sea level (in miles). If a city has an atmospheric pre

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: The atmospheric pressure P in pounds per square inch (psi) is given by P = 14.7 e−0.21 awhere a is the altitude above sea level (in miles). If a city has an atmospheric pre      Log On


   



Question 716431: The atmospheric pressure P in pounds per square inch (psi) is given by
P = 14.7 e−0.21 awhere a is the altitude above sea level (in miles). If a city has an atmospheric pressure of 11.21 psi, what is its altitude? (Recall that 1 mi = 5,280 ft. Round your answer to the nearest foot.)

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The atmospheric pressure P in pounds per square inch (psi) is given by
P = 14.7 (e−0.21 a) where a is the altitude above sea level (in miles). If a city has an atmospheric pressure of 11.21 psi, what is its altitude? (Recall that 1 mi = 5,280 ft. Round your answer to the nearest foot.)
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11.21 = 14.7*e^-0.21a
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e^(-0.21a) = 0.7626
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Take the natural log of both sides to get:
-0.21a = -0.2710
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a = 1.2906 miles
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a = 1.2906*5280 = 6814 feet
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Cheers,
Stan H.
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