I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?

Move three sticks of the spiral below to form a square.

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

If you were to put a coin into an empty bottle and then insert a cork into the neck, how could you remove the coin without taking out the cork or breaking the bottle?

At my favorite fruit stand,
an orange costs 18,
a pineapple costs 27,
and a grape costs 15.
Using the same logic, can you tell how much a mango costs?

Solve this riddle by finding the odd one out from the rest.

Can you find the missing number in the third row?
35 20 14
27 12 18
5 2 ?

Can you move 2 matchsticks to form four equal sized squares.

Why Aeroplane windows are round?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?