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

When I got four, I have it none.
When I got two, I have it some.
When I got none, I have it all.

What is it?

Which Burger Is Different in below image?

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?

If it took eight men ten hours to build a wall, how long would it take four men to build it?

What can jump higher than a building?

Can you find a pattern and the missing number in the series given below?

100, 155, 258,? , 584, 819.

Rearrange the letters in "new door" to make one word.

Six people park their car in an underground parking of a store. The store has six floors in all. Each one of them goes to a different floor. Simon stays in the lift for the longest. Sia gets out before Peter but after Tracy. The first one to get out is Harold. Debra leaves after Tracy who gets out on the third floor.

Can you find out who leaves the lift on which floor?

Solve the alphametic puzzle by replacing the alphabet with the number.

S T O R M +
S O L E S
=========
T O W E L
=========