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?

Find the missing number in the sequence below:

How many triangles can you count in the figure given?

I am lying and I always lie. Tell me whether I am lying or telling the truth.

Pronounced as one letter,
And written with three,
Two letters there are,
And two only in me.
I am double, I am single,
I am black blue and grey,
I am read from both ends,
And the same either way.

I have a five and a three-gallon jar. Assuming there is an infinite supply of water, how can I measure one-gallon water?

A word I know,
Six letters contain,
Subtract just one,
And twelve is what remains.

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

You are stuck on an island where you have nothing. You find four pieces of paper somewhere on the island. What will be your strategy to escape from the island safely?

PS: No other resource is available to you on the island, neither can you build anything.

A brand new Mobile Phone was on sale at 20% as a promotional offer. By what per cent must the Mobile price be increased to sell it at the original price again?