Equilibrium constants do not change with the amount of concentration so while the second reaction is multiplied by three is does not change the Kp.
The flipping of the reaction affects the equilibrium constant.
When the reaction is flipped the Kp is reciprocated:#(1/(Kp))# becuase Kp is #-log((Products)/(reactants))# but if the reaction is flipped reactants become products and so on. Since we have the Kp for the forward we will do #1/(2.26x10^4)= 4.4 x10^-5# This answer makes sense since previously we had a big Kp which means this reaction favors products but when the reaction is flipped the reaction favors the reactants ( what used to be the products) and that's why is it smaller since it favors reactants again recalling that the equilibrium constant is #-log((Products)/(reactants))# so a favor in reactants will make a large denominator and thus a small fraction
