The reaction equation would be:
C3H8 + 5*O2 => 3*CO2 + 4*H2O.
For 1 mol C3H8 react there will be 3 mol CO2 formed. The molecular weight for C3H8 would be: 2*12+ 8*1= 44g/mol.
The amount of CO2 molecule formed would be: 295 g / (44g/mol) * (3 mol/1 mol)= 20.11 mol
For STP condition, a mol of an ideal gas will have 22.4 liters volume. The volume of the gas would be: 20.11 mol* (22.4l/mol)= 450.54 liters