Answer:
so pressure in A must be one third the pressure in B
Explanation:
We shall apply gas law to the cylinders A and B . Since their quantity are same so their no of  mole will also be same .
For cylinder A
Temperature T , volume 3V , pressure  Pâ , no of mole = n
so
Pâ X 3V = n R T
For cylinder B
Temperature T , volume V , pressure  Pâ ,no of  mole = n
so
Pâ X V = n R T
From the two equation above
Pâ X 3V = Pâ X V
[tex]\frac{P_1}{P_2}=\frac{1}{3}[/tex]
Pâ = Pâ / 3
so pressure in A must be one third the pressure in B