How can a man go eight days without sleep?

Complete the table series riddle by finding the number that can replace "??".

Can you decipher the two rows to find the hidden word?

Your last good ping-pong ball fell into a narrow metal pipe embedded one foot deep in concrete.
How can you get it out undamaged, if all the tools you have are your tennis paddle, shoe laces, and plastic water bottle, which does not fit into the pipe?

I have a big mouth and I am also quite loud! I am NOT a gossip but I do get involved with everyone's dirty business.

I throw two dice simultaneously.

What is the probability of getting a sum as 9 of the two numbers shown?

Be active and find the killer in the picture Riddle below.

Can you find the missing piece of the Porsche?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

Three fair coins are tossed in the air and they land with heads up. Can you calculate the chances that when they are tossed again, two coins will again land with heads up?