Captain Jack Sparrow was known for his uncanny ability to sink enemy ships. Based on statistics from his past battles, each of his cannon fires had a probability of 1/2 to direct hit and sink the target. The statistic also showed that when the fire did not result in a sinking, it nevertheless caused less severe damage to an enemy vessel with probability of 1/4, and two damaging explosions are sufficient to sink a ship. The remarkable part is that Captain Sparrow only missed his adversary 1/4 of the time. On the battle against Davy Jones, Captain Sparrow had only one working cannon on his ship with four cannon balls. Assume that Captain Sparrow stop firing when the ship sunk although there were cannon balls left. On the other hand, if Captain Sparrow still could not sink Jones' ship, he would fire until the last one. With the statistics above in mind, what is twhat is the probability that Captain Sparrow would be able to sink Jones' ship?