According to the ideal gas equation, the ratio of the initial pressure to the initial temperature should be equal to the ratio of the test pressure to the final tperature,i.e. P1T1=P2/T2
P1=2.250atm
P2=1.55atm
T1=335Kelvin (62°C+273)
T2=?
2.25atm/335K=1.55atm/T2
T2=(1.55atm*335K)/2.25
=230.778Kelvin
=-42.222°C