What number when divided in half becomes zero?

The centre of the third figure is empty. What digit should fit inside?

I am the fastest animal but cannot climb the tree. What am I?

In two decks of cards, what is the least amount of cards you must take to be *guaranteed* at least one four-of-a-kind?

Replace the letters of words with a number so that the below equation holds true

BASE +
BALL
---------
GAMES
----------

After teaching his class all about Roman numerals (X = 10, IX=9 and so on) the teacher asked his class to draw a single continuous line and turn IX into 6. The teacher's only stipulation was that the pen could not be lifted from the paper until the line was complete.

You are provided with a grid (as shown in the picture). Can you fill the squares with numbers 1-8 in a manner that none of the two consecutive numbers are placed next to each other in any direction (vertically, horizontally or diagonally?)

Which is heavier: a ton of bricks or a ton of feathers?

How many letters are in the alphabet?

Six glasses are in a row. The first three are filled with milk and the last three are empty. By moving only one glass, can you arrange them so that the full and the empty glasses alternate?