A flight attendant wants to change the temperature of the air in the cabin from 18.0° C to 23.3° C without changing the number of moles of air per m3. What fractional change in pressure would be required?

Answer 1

P/T= constant or

P1/T1=P2/T2

or
T2/T1=P2/P1

I am not certain what you mean by fractional change, if it is P2/P1, you are done. Now if you mean as fractional change

(P2-P1)/P1 you have to subtract one from P2/P1

ie (P2-P1)/P1= P2/P1 - 1

Answer 2

i worked the problem out using that formula but i kept getting the wrong answer

(23.3-18)/18=0.294