You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

Can you find the ages of a son, father and grandfather based on the following facts?
The sum of the ages of grandfather, father and son is 140 years.
The age of the son in months is the same as the grandfather in years.
The age of the son in days is the same as the father in weeks.

What is a word made up of 4 letters, yet is also made up of 3. Sometimes is written with 9 letters, and then with 4. Rarely consists of 6, and never is written with 5.

Can you replace the question mark with the correct number in the below table sequence?

There were five men at church, and it started raining while they were outside. The four that ran still got wet, but the one that was still stayed completely dry. Why did he stay dry?

There was a blind man. He had four socks in his drawer either black or white. He opened it and took out two socks. Now the probability that it was a pair of white socks is 1/2.

Can you find out the probability that he had taken out a pair of black socks ?

If a wheel has 54 spokes, how many spaces are there between the spokes?

If an electric train is travelling south, then which way is the smoke going?

I am a prime number.
The double of myself is equal to the square of me.

which number am I?

Forwards I am heavy, backward I am not. What am I?