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 occurs twice in a week, once in a year but never in a day?

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

Can you count the number of blocks in the picture below?

Identify The phrase in the picture.

There are three light switches outside a room. One of the switches is connected to a light bulb inside the room.
Each of the three switches can be either 'ON' or 'OFF'.

You are allowed to set each switch the way you want it and then enter the room(note: you can enter the room only once)

Your task is to then determine which switch controls the bulb?

Place a mathematical symbol between the numerals 5 and 9 in such a way that the resulting number is greater than 5 but smaller than 9.

I am eight letters long - "12345678"
My 1234 is an atmospheric condition.
My 34567 supports a plant.
My 4567 is too appropriate.
My 45 is a friendly thank-you.
My 678 is a man's name.

What word am I?

If you're 8 feet away from a door and with each move you advance half the distance to the door. How many moves will it take to reach the door?

A maths symbol is hidden in the below Bar Graph. Can you decipher it?