Please show your process step by step, and also a diagram of the reaction/reactor itself. I'm extremely confused on how to even set this one up. Thanks for any help.

An equimolar mixture of propane and butane is fed to a combustion reactor with 100% excess air. Both the propane and butane undergo complete combustion with fractional conversion of 0.8 and 0.75, respectively. If the incoming mixture is fed at 5 kg/s, determine the exiting molar flowrates from the reactor in mol/s