If 21x = 79x, what is the value of x?

Find the smallest sentence with all the English alphabet.

Find three whole, positive numbers that have the same answer when multiplied together as when added together.

You have a 12 liters jug full of water. You have two empty 8 liters and 5 liters jug. How can you divide the water into two equal parts using these jugs?

Steffi's daughter Jazelle needs to be picked up from school every day.
Steffi asks one of her colleagues to pick up Jazelle from the school. Steffi devised a password system to confirm that Jazelle goes with the correct colleague only.

The password on Monday was SJM16.
The password on Wednesday was TAW39.

What will the password be for Friday?

I travel all around the world but always stay in the corner. What am I?

Use only one mathematical symbol and all numbers (0-9) to get a sum of 99

Solve the equation by replacing the alphabet with numbers.

MOM + MOM + NO = BOOK=

The first box has two white balls. The second box has two black balls. The third box has a white and a black ball.

Boxes are labeled but all labels are wrong!

You are allowed to open one box, pick one ball at random, see its colour and put it back into the box, without seeing the colour of the other ball.

How many such operations are necessary to correctly label the boxes?

You have three orange, two pink and five purple balls in the drawer beside your bed. There is no electricity and the room is entirely dark. How many balls must you take out to ensure at least one ball of each colour at least?