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

Question

P = 14.7 e−0.21 awhere a is the altitude above sea level (in miles). If a city has an atmospheric pressure of 11.11 psi, what is its altitude? (Recall that 1 mi = 5,280 ft.

Answer 1

just solve for a:

14.7 e^(-0.21a) = 11.11
e^(-0.21a) = 0.7558
-0.21a = ln 07558 = -0.28
a = 4/3