Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

If you drop me I’m sure to crack, but give me a smile and I’ll always smile back. What am I?

Once while in his court, King Akbar asked Birbal to write something on a wall that makes one sad when read in good times and makes one happy when read in sad times.

He took only a few moment and wrote something that fit the requirements. What did he write?

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

The following alphametic has only one solution. Can you find it?
ENLIST + SILENT + LISTEN = ANAGRAM

PS: You may start the number from 0.

I have an apple tree , number of apple in this tree get doubles every week.

On 30th week , the tree gets completely filled with apples :-)



Can you tell me , on what week does my tree is half covered with apples ?

Why is a river so rich ?

I had an infinite supply of water and 5 litres and 3 litres jars.

How would you measure exactly 4 litres in the least number of steps?

Can you place six X (crosses) in below board without making three in a row in any way ?