From equation. Initial mole mole at equilibrium X10(1−a)⇌Y0a+Z0a Kp1=pXpY×pz=[1+α1−α]p1[1+αα×p1][1+αα×p1]KP1=1−α2α2p1 From equation Initial mole mole at equilibrium A10(1−a)⇌2B02a Kp2=[1+α1−α]p2[1+α2α⋅p2]2=1−α24α2p2 From Eqs (i) and (ii) KP2KP1=4p2p1 ⇒⇒19=4p2p1∴p2p1=136