If you toss a coin 10 times and it lands heads up every time, what are the chances it will land heads up if you toss it again?

What has many keys but can’t open a single lock?

For this puzzle, you might have to find logic in something illogical. But hey, it's fun and a healthy little break from your strenuous puzzle-solving sessions.

Can you decipher the meaning in the following cluster of letters?

ITIT,NCENTCENT

Solve the following series:
AZ, GT, MN, __, YB

A boy and a girl are sitting on the porch.
"I'm a boy," says the child with black hair.
"I'm a girl," says the child with red hair.
If at least one of them is lying, who is which?

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

A four-digit number (not beginning with 0) can be represented by ABCD. There is one number such that ABCD=A^B*C^D, where A^B means A raised to the B power. Can you find it?

Which wheel of car does not rotate when you turn your car right?

There are are five things wrong with this sentence; only geniuses will be able to to spot all of the mitstakes

A boy and his father are caught in a traffic accident, and the father dies. Immediately the boy is rushed to a hospital, suffering from injuries. But the attending surgeon at the hospital, upon seeing the boy, says 'I cannot operate. This boy is my son.' How is this situation explained?