Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.

How many letters are in the alphabet?

What's the only room from which no one can enter or leave

There is a straight highway. Four different villages lie on that highway. The distance between them is different. The third village is 60km away from the first village; the fourth is 40 km away from the second; the third is 10 km near to the fourth that it is to the second.

Can you calculate the distance between the fourth and the first village ?

Three men in a cafe order a meal the total cost of which is $15. They each contribute $5. The waiter takes the money to the chef who recognises the three as friends and asks the waiter to return $5 to the men.

The waiter is not only poor at mathematics but dishonest and instead of going to the trouble of splitting the $5 between the three he simply gives them $1 each and pockets the remaining $2 for himself.

Now, each of the men effectively paid $4, the total paid is therefore $12. Add the $2 in the waiters pocket and this comes to $14. Where has the other $1 gone from the original $15?

This is a classy optical illusion puzzle. What more you can find except bricks in the image below?

How many points are there on the globe where, by walking one mile south, then one mile east and then one mile north, you would reach the place where you started?

Complete the series by replacing "?" with the correct number.

ST ND RD TH '?'

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

Why Aeroplane windows are round?