I am white when I am dirty, and black when I am clean. What am I?

Find out a multi-digit number that if multiplied by the number 9 or any of its multiplications products (i.e. 18, 27, 36, 45,..) will result in the multiplication factor repeated (n) number of times.

There is something which you can be arrested for attempting but not for successfully completing.

Solve the following series:
AZ, GT, MN, __, YB

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.

Two batsman each on 94 runs. Seven runs needed to win in last 3 balls. Both make 100*. How?

Count the squares in the matchstick puzzle below?

using four eights (8) and a one (1) and one mathematical symbol , create the number 100

What English word has three consecutive double letters?

You need to complete the maze by entering from the entrance marked below in the figure near the yellow circle, bottom left and leaving from the exit point near the green circle, bottom middle.

Rule of Game: You can move only by exchanging green and yellow circles.