The atmospheric pressure P in pounds per square inch (psi) is given by

Question

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 12.31 psi, what is its altitude? (Recall that 1 mi = 5,280 ft. Round your answer to the nearest foot.)

Answer 1

14.7 e^(-.21a) = 12.31
e^(-.21a) = 0.837
-.21a = ln 0.837 = -0.177
a = 0.845 mi = 4462 ft