You are given 16 witch hats. The hats are divided in four different colours – red, blue, green and yellow. Every colour has been assigned to four hats. Now each of the hat will be glued with a label of an arithmetic sign – ‘+’, ‘-‘, ‘x’ or ‘/’. But you can label one sign only once on one colour. In such an arrangement, the hats can be uniquely defined by its colour and symbol.

Can you arrange all the 16 hats in a 4x4 grid in a fashion that no two rows and columns have a repetition of colour or sign?
We have arranged four hats in the below picture to assist you.

I am lying and I always lie. Tell me whether I am lying or telling the truth.

What is the largest number you can write with just 3 digits?

I inserted a coin in a bottle and closed its mouth with the help of a cork. Now, I was able to take the coin out from the bottle without taking out the cork or breaking the bottle. Can you tell me how I did it?

Create a number using only the digits 4,4,3,3,2,2,1 and 1. So i can only be eight digits. You have to make sure the ones are separated by one digit, the twos are separated by two digits the threes are separated with three digits and the fours are separated by four digits

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

You need to arrange three 7 and mathematical symbols to form number 1?

What word is pronounced the same if you take away four of its five letters?

Can you find out the remainder when 3^300 is divided by 5?

Can you convert the number zero(0) into a positive number using just one mathematical operator ?