Sure, you can take the lazy shortcut and google the answers
to these riddles, but hey, live a little, have the courage to
honestly challenge your own mental prowess and academic
competence in logic, eh? See if you can get all 5 questions correct
within 10 minutes. Time yourself!
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Updated/Edited :
I initially thought of 'marking' the replies here and scoring
them, all of them one-by-one; but as it turns out (and you can see
this for yourself), the way the replies are posted, (eg.
"solution already posted in riddles forum", instead of a
proper explanation in your own words), it makes properly
marking and scoring the replies quite difficult, if not impossible.
Besides, I can tell you guys are having more fun discussing the
riddles with each other, rather than just having your replies
marked, and obtaining a score.
So to this end, I'll not 'mark' or score you guys, but instead,
leave you to continue discussing and debating these rather
brilliant riddles. Rest assured, these are not 'nonsense' riddles
without answers; everyone of these 5 riddles are valid
exercises in logic, IQ, mathematics and intuition.
Continue having fun! 
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Number of Qns correct (must be within 10 minutes, and valid
only if you're 100% honest with yourself) :
1 - U Cockonaden -
沒脸見人…呸!
2 - Ok lah just pass
- 免免強強可以.
3 - U Da Power - 好厲害哦!
4 - Legendary - 天下無敵 神話崛起
5 - Godlike - 以天下人之心為心 以天下人之意治天下
Q1 to Q5, In increasing order of difficulty :
1) The "Chicken" Riddle
A man bought a chicken for $8, sold it for $9, bought it back
for $10, and sold it for $11. How much profit did he make?
2) The "Three Men & A Waiter" Riddle
Three men ate dinner at a restaurant. The bill came up to $30.
Each paid $10. After they left the restaurant, the manager realized
there was a mistake in the bill. The bill was merely $25. He sent a
waiter with $5 to pay back the 3 guys, who had gone their separate
ways. As the waiter ran after the 3 guys, he realized they had
split up, and he thought to himself, "How the heck am I supposed to
pay each person 5/3 dollars? Heck, I'll just give each guy a dollar
each, and keep $2 for myself as tips!".
So each guy paid $10 - $1 = $9. Three guys paid $9 x 3 = $27 in
total. Plus the $2 the waiter kept, that's $27 + $2 = $29. What
happened to the missing dollar?
3) The BoyBoy-BoyGirl-GirlBoy-GirlGirl Riddle
You and a friend are standing in front of two houses. Your
friend informs you, "In each house lives a family with exactly two
children."
"For the family on the left, at least one of the two
children is a boy", your friend tells you.
"The family on the right has a 7-year old boy, and they just had
a new baby a month ago," he explains.
"Does either family have a girl?" you ask.
Your friend smiles, "Pick the family that you think is more
likely to have a girl. If they do have a girl, I'll buy you
dinner."
Which family should you pick, or is it the case that it does not
matter? Explain using probability mathematics.
4) The "Monty Hall Goat Riddle" aka "Marilyn vos Savant and
the Goats"
A thoroughly honest game-show host has placed a car (the winning
prize) behind one of three doors. There is a goat (consolation
prize) behind each of the other doors. You have no prior knowledge
that allows you to distinguish among the doors. "First you point
toward a door," he says. "Then I'll open one of the other doors to
reveal a goat. After I've shown you the goat, you make your final
choice whether to stick with your initial choice of door, or to
switch to the remaining door. You win whatever is behind the
door." Should you switch doors? Explain using logic,
mathematics, or compelling intuitive arguments.
5) Inspector Craig Visits Transylvania
Inspector Craig of Scotland Yard was called to Transylvania to
solve some cases of vampirism. Arriving there, he found the country
inhabited both by vampires and humans. Vampires always lie and
humans always tell the truth. However, half the inhabitants, both
human and vampire, are insane and totally deluded in their beliefs:
all true propositions they believe false, and all false
propositions they believe true. The other half of the inhabitants
are completely sane: all true statements they know to be true, and
all false statements they know to be false. Thus sane humans and
insane vampires make only true statements; insane humans and sane
vampires make only false statements. Inspector Craig met two
sisters, Lucy and Minna. He knew that one was a vampire and one was
a human, but knew nothing about the sanity of either. Here is the
investigation:
Craig (to Lucy) :Tell me about yourselves.
Lucy : We are both insane.
Craig (to Minna) : Is that true?
Minna : Of course not!
From this Craig was able to prove which of the sisters was the
vampire. Which one was it?