Combined gas law is the combination of Charles's law, Boyle's law, and Gay-Lussac's law. It states that the ratio between the pressure-volume product and temperature is a constant. In this calculator, the initial and final volume, pressure, temperature can be calculated alternatively with the other known values.
If the initial and final volume is 12, 2, initial and final pressure is 10, 7 and initial temperature is 5,
Tf = (Ti x PfVf) / PiVi
= (5 x 7 x 2) / (12 x 10)
Hence, final temperature is 0.58