Guidance on finding the pressure and density of nitrogen

[kawf]

Homework Statement

Calculate the pressure and density of nitrogen at which there is a 15% error in the ideal gas equation of state for a plane flying in air of temperature 250 K

Homework Equations

P = rho RT
Pv = RT

The Attempt at a Solution

Little confused on how to approach the problem. Any guidance is appreciated.

 

[Kushal]

i would suggest that since air is made up of about 78% nitrogen, you could substitute the nitrogen with air. anyway, there is already a 15% error in the equation. the error due to the substitution of nitrogen by air should not be very significant.

i might as well be wrong!