What seven-letter word has hundreds of letters in it?

How many people must be gathered together in a room, before you can be certain that there is a greater than 50/50 chance that at least two of them have the same birthday?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?

There are nine dots in the picture that has been attached with this question. Can you join all the dots by drawing four straight lines without picking up your pen?

I have one of the three numbers: 1, 2, or 3 in my mind. I speak only truth. You can ask me just one question for which I will only reply in yes or no or don't know. What question will you ask from me so that you are able to know the number?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

What work can one never finish?

There are nine letters in the below-given diagram. You have to form a nine-letter word using these letters.

Can you place three balls such that the equation shown in the picture holds true?

What does this simple rebus mean?