equilibrium constant for the reaction mentioned below at a certain tempereture is 0.914 NO2 + NO ⇌ N2O + O2 if initially 0.4 moles of NO2 is available how many moles of NO should be added to the vessel to have 0.15 mol of N2O(g) at equilibrium ?

Question

equilibrium constant for the reaction mentioned below at a certain tempereture is 0.914  NO2 + NO ⇌ N2O + O2  if initially 0.4 moles of NO2 is available how many moles of NO should be added to the vessel to have 0.15 mol of N2O(g) at equilibrium ?