'Fifty' in the Bible

Then said Zeresh his wife and all his friends unto him, Let a gallows be made fifty cubits high, and in the morning speak thou unto the king that Mordecai may be hanged thereon: then go thou in merrily with the king unto the banquet. And the thing pleased Haman; and he caused the gallows to be made.

Then said Harbonah, one of the chamberlains that were before the king, Behold also, the gallows fifty cubits high, which Haman hath made for Mordecai, who spake good for the king, standeth in the house of Haman. And the king said, Hang him thereon.