The pressure of the gas would increase.
Explanation:
Using the ideal gas formulae we can evaluate this fact;
PâVâ/Tâ = PâVâ/Tâ
We can assume that the volume is reduced by half (the Tâ and Tâ will cancel out because they remain constant);
PâVâ = Pâ * 0.5Vâ
PâVâ/0.5Vâ = Pâ
Pâ/0.5 = Pâ
You can observe that the pressure will also increase â diving a number by a fraction or decimal number increases the resultant value. In this case, the pressure will increase by 2 fold