What is both possible and impossible at the same time?

Find the missing number in the sequence below:

A very interesting trivia question for all.

Why do men's shirts have their buttons on the right side and women's have buttons on the left-hand side?

Identify the hidden meaning behind this picture?

A man dies of old age on his 25 birthday. How is this possible?

Two-person want to cross a river. Only one boat is present on the riverside that can carry only one person at a time.

However, they still manage to cross the river. How is it possible?

Two girls were born to the same mother, on the same day, at the same time, in the same month and year and yet they're not twins. How can this be ?

While house hunting in London, I came across a very good leasehold property Discussing the lease the landlady told me:

'The property was originally on a 99 years lease and two-thirds of the time passed is equal to four-fifths of the time to come. Now work it out for yourself and see how many years are to go!

Can you tell a 3D object that has just two surfaces?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?