Question: If you have an 11 minute and 13 minute hourglass, how can you accurately time 15 minutes?
Answer: Start both hourglasses then when the 11 minute hourglass has finished immediately flip it again. When the 13 minute hourglass runs out the 11 minute hourglass will have 9 minutes left, so flip it and it will last another 2 minutes, 13 minutes + 2 minutes = 15 minutes.
Question: Two men were on a ship. They were both facing opposite directions, one facing east and the other facing west. But, they were both seeing each other. *WITHOUT MIRRORS* How is this possible?
Answer: They were both facing each other