Why Aeroplane windows are round?

Can you make four (4) nines (9) equal 100?

A 52% bias toss for head using the 51% tail bias coin was done to obtain a fair result.

Can you find how bias is the floor in this case?

How can you leave a room with two legs and return with six legs?

There were two grandmothers and their two granddaughters.
There were two husbands and their two wives.
There were two fathers and their two daughters.
There were two mothers and their two sons.
There were two maidens and their two mothers.
There were two sisters and their two brothers.
Yet there are only six, who are buried here,
All are born legitimate and relationships clear.
How can this happen?

Can you find the missing piece of the Porsche?

A man always keeps a spare tyre in his car. To make full use of all the five tyres, he changes the tyres in a manner that for a distance of 1, 00,000 km, each of them runs the same distance.

Can you calculate the distance travelled by each tyre on that journey?

Eight of us go fourth, not back, to protect our king from an attack. What are we?

Can you name some countries which do not have the alphabet 'A' in them?

Luis Garavito killed Density x Volume.

Who is Luis Garavito ?