There was a contest where an apple, a pear, a banana and an orange were placed in four closed boxes.  One hundred and twenty-three people participated, who each guessed which fruit was in which box.  Shortly after the boxes were opened, it was revealed that thirty-one people guessed two fruits correctly, thirty-nine guessed one correctly, and forty-three people guessed none correctly.
Question:  How many of the participants guessed three fruits and four fruits correctly?

Answer:  If only three of the four fruits were guessed correctly, then the fourth one is also correct.  Therefore, no one guessed only three fruits correctly which means that ten people got it right (123-43-39-31=10). This is a hard riddle because many people fail to do the math properly.

There once was a man who was born before his father, killed his mother, then, later on, married his sister.  Yet, there was nothing wrong with what was done.  Why is that?

Answer:  To solve this riddle, you need to view it from an alternate angle.  The man's father was in the delivery room when he was born, his mother died while giving birth to him, and he later became a minister and officiated at his sister's wedding ceremony.

Are you able to find the names of three trees which are hidden in the following sentences?  The letters are already in order.  Are you able to find them?  At this supermarket, we get ham from a hog any day.  The workers will help in every way they can. They were faced with two very similar choices, both of which ended badly. 

Answer:  Mahogany, pine, larchFor those of you who did not figure it out, the answers lie between the words "from a hog any, help in every, and similar choices."This hard riddle is more like reading between the words than the lines.

Can you figure out the sequence in the following numbers?1, 11, 21, 1211, 111221, 312211 _______

Answer:  13112221.  Each number sequence is a verbal representation of the number before it.  Therefore, beginning with 1, the following number is 11, because there is one 1.  The next number in 21 because there are two 1s in the number 11.  You repeat this pattern until you get the answer 13112221.  This because in the previous number 312211, there is one 3, one 1, two 2s, and two 1s (13112221).

Use all the letters in the following sentences can be restructured to create well-known phrases.
Strong lion's share almost gone.I don't admit women are faint.It rocks the broad flag of the free.

Answers:A rolling stone gathers no moss.Time and tide wait for no man.Birds of a feather flock together.

A Roman Emperor had a grand banquet prepared for himself and his courtiers.  On the menu were 22 Dormice, 30 Flamingoes, 40 Roast Parrots, and 40 Larks' Tongues.  How many portions of Boiled Ostrich were served?

Answer:  42.  Each vowel of the word is worth two and each consonant is worth four.  Therefore, in the words 'boiled ostrich," the vowels add up to 10 and the consonants 32.

On a sunny afternoon, three men rode over the Sahara Desert in a hot air balloon.  Sixty minutes into the trip, the balloon begins to descend, slowly losing altitude.  One month later, a naked man is found in the desert dead and holding onto half a toothpick.  What happened to the man in this hard riddle?

Answer:  As the balloon lost altitude, the three men attempted to reduce the weight by stripping off their clothes.  When that didn't work, they drew sticks to determine who will jump off and who will stay onboard.  The man found in the desert is the one who stayed onboard by drawing the shortest stick.

An old man passes away, leaving behind his two sons.  In his will, the two sons are instructed to race against each other with their horses.  The recipient of his inheritance will be the son with the slower horse.  The two sons race each other, but they are both holding back.  To solve this dilemma, they visit a wise old man for help.  This time they race each other again, but at full speed.  What did the wise old man instruct the brothers to do?

Answer:  The old man told them to switch horses.  By doing so, whoever wins the race will get the inheritance because they will still technically be the owner of the slower (losing) horse.

You are trying to escape a labyrinth.  There are three doors to choose from.  The left door leads to a raging fire.  The door in the center leads to a dangerous assassin.  The door on the right, on the other hand, takes you to a hungry lion which hasn't eaten in three months.  Which door would you take?

Answer:  This hard riddle isn't so hard if you breathe, relax and think about your options. You take the door on the right because a lion which hasn't eaten in three months would be dead.

Four people must cross a river using a narrow bridge which can only support two people at a time.  It is nighttime, and there is only one torch which they must use to light their way across the bridge.  Person A can cross the bridge in one minute, person B in two minutes, person C in five minutes and person D in eight minutes.  When two of the people cross the bridge together, they must move at the same pace as the slower person.  Question:  Are they all able to cross the bridge in 15 minutes or less?

Answer:  Yes.  They can do so in precisely 15 minutes.  To do so, they must do this:
This hard riddle may seem hard to solve at first, but here's what needs to happen. In the first two minutes, persons A and B cross the bridge, then A brings the light back, which takes one minute.Then, C and D cross the bridge together, and B goes back to bring the light.  They do this and a total of thirteen minutes has now passed.Lastly, A and B cross the bridge together again, which takes up two minutes of their time.