Answer : The new volume of gas will be 117 ml.
Step-by-step explanation:
Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.
The combined gas equation is,

where,
= initial pressure of gas = 50 kPa
= final pressure of gas = 225 kPa
= initial volume of gas = 400 ml
= final volume of gas = ?
= initial temperature of gas =

= final temperature of gas =

Now put all the given values in the above equation, we get the final pressure of gas.


Therefore, the new volume of gas will be 117 ml.