Riddle: Find four numbers, the sum of which is 45, so that if 2 is added to the first number, 2 is subtracted from the second number, the third number is multiplied by 2 and the fourth number is divided by 2, then the four numbers so produced are all the same. What are the four numbers?
Answer:  8 + 2 = 10 12 - 2 = 10   5 x 2 = 10 20 ÷ 2 = 1045
Riddle: A forest exists somewhere on Earth. This forest has no life except for trees. After a storm, a tree was hit by lightning and falls. What sound would it make?
Answer: None. Sound does not exist if it is unheard.
Riddle: How many times does the long hand of the clock pass the short hand between midnight one day and midnight the following day? As both hands are together at the starting time of midnight this does not count as a pass.
Answer: 21.
Riddle: What have these words in common? ASPIRATED GRANGERS PRELATES SWINGERS CHASTENS
Answer: All can be diminished by one letter (from begining and end alternately) forming a new word each time.
Riddle: Suppose you want to send in the mail a valuable object to a friend. You have a box which is big enough to hold the object. The box has a locking ring which is large enough to have a lock attached and you have several locks with keys. However, your friend does not have the key to any lock that you have. You cannot send the key in an unlocked box since it may be stolen or copied. How do you send the valuable object, locked, to your friend - so it may be opened by your friend?
Answer: Send the box with a lock attached and locked. Your friend attaches his or her own lock and sends the box back to you. You remove your lock and send it back to your friend. Your friend may then remove the lock she or he put on and open the box.
Riddle: A dog had three puppies, named Mopsy, Topsy and Spot. What was the mothers name?
Answer: What
Riddle: The following numbers share a unique property: 1961 6088 6119 8118 6699 6009. What is it?
Answer: Each number reads the same when viewed upside down.
Riddle: Five hundred begins it, five hundred ends it, Five in the middle is seen; First of all figures, the first of all letters, Take up their stations between. Join all together, and then you will bring Before you the name of an eminent king. Who am I?
Answer: DAVID (Roman numerals)
Riddle: As a whole, I am both safe and secure. Behead me, and I become a place of meeting. Behead me again, and I am the partner of ready. Restore me, and I become the domain of beasts. What am I?
Answer: Stable.
Riddle: Sally, Lisa, and Bernadette are triplets. But Sally and Lisa share something that Berandette does not. What is it?
Answer: The letter 'L' in their names.