1 + 9 + 8 = ?
considering, 28 + 8 + 92 = 10

A chess tournament is taking place on knock-out terms (the one who loses the match is out of the game).
(a) If 10 matches are played in total, how many players participated?
(b) If 20 players took part in the tournament, how many matches were played?

Can you count the number of triangles in the given picture?

What runs around the whole yard without moving?

A tree doubled in height each year until it reached its maximum height over the course of ten years. How many years did it take for the tree to reach half its maximum height?

Okay before we begin with the puzzle, do keep in mind that you have to answer it quickly.

You are participating in a car race. Seeking the perfect moment, you overtake the second person in the race. What positions are you in now?

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?

Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

There are are five things wrong with this sentence; only geniuses will be able to to spot all of the mitstakes

Move four matchsticks to the below square to form three squares?