How can a man go eight days without sleep?

You have two hour glasses one measures 7 minutes and the other measures 4 minutes.
Using these two-hour glasses, you need to measure exactly 9 minutes.

How come?

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

What can you deduce from the following BrainBat?

CRY
LMKI

Can you complete the sequence puzzle?

AR TA GE CA LE VI LI _

Old Mr.Rakesh was found dead in his bedroom by young Manish.
Manish recounted his dismal discovery to Detective FBI detective Donald, who happens to be around the scene.

'I was walking by Mr. Rakesh's house when I thought I would just pop in for a visit. I noticed his study light was on and I decided to peek in from the outside to see if he was in there. There was frost on the window, so I had to wipe it away to see inside. That is when I saw his body. So I kicked in the front door to confirm my suspicions of foul play. I called the police immediately afterwards.'

With a clue from Detective FBI Detective Donald, the police officer immediately arrested Manish for the murder of Mr Rakesh. How did he know Manish was lying?

You find yourself in a strange place guarded by two guards.One of the guard always say truth while other always lies.You don't know the identity of the two.You can ask only one question to go out from there. What should you ask?

In Greek mythology, the Sphinx sat outside of Thebes and asked this riddle of all travellers who passed by. If the traveller failed to solve the riddle, then the Sphinx killed him/her. And if the traveller answered the riddle correctly, then the Sphinx would destroy herself. The riddle:

What goes on four legs in the morning, on two legs at noon, and on three legs in the evening?

Oedipus solved the riddle, and the Sphinx destroyed herself.

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?

What runs around the whole yard without moving?