To solve this problem, we can use the combined gas law equation:
(P₁ x V₁)/T₁ = (P₂ x V₂)/T₂
Where P₁, V₁, and T₁ are the initial pressure, volume, and temperature of the gas, respectively. P₂ is the pressure we want to find, V₂ is the same as V₁, and T₂ is the final temperature of the gas.
Substituting the given values, we get:
(241 KPa x 1,250 L)/683 K = (P₂ x 1,250 L)/432 K
Simplifying and solving for P₂, we get:
P₂ = (241 KPa x 1,250 L x 432 K)/(683 K x 1,250 L) = 152.4 KPa
Therefore, the pressure of the gas when the temperature decreased to 159C is approximately 152.4 KPa.