Name a key which is hardest to turn.

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?

Replace the question mark with the correct number, given the pair of numbers exhibits a similar relationship?

? : 3839 :: 11 : 1209

Can you identify if it's a murder or a suicide ?

John and his wife were living in a rural place. On a particular day, John's wife fell ill and he called the local doctor. When the doctor picked up, he said, "Doctor, my wife is ill. She might have appendicitis."

"This can't be possible! I took out her appendix two years ago myself," the doctor explained.

When diagnosed, John's wife was found to have appendicitis. How can this be possible?

You need to move three matchsticks to form three squares. Can you do it?

I know a ten-letter word in the English language which can be typed using only the top rows of the computer keyboard.

what does this picture(rebus) riddle means ?

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?