What is next number in the pattern below:

131 517 192 123 ?

Why do you find that most of the buildings are deprived of the 13th floor?

You knock a Table over in the library, and suddenly 20 eyes are looking at you.

I have Rs.50 and I spend it in the way as below.

What is the word or phrase?

In the following picture, E is going to slide the object down and as per the terrain and the physics, the round object is going to travel all the way till the end. Now, can you analyze who all people will die when it happens?

An infinite number of mathematicians are standing behind a bar. The first asks the barman for half a pint of beer, the second for a quarter pint, the third an eighth, and so on. How many pints of beer will the barman need to fulfill all mathematicians' wishes?

Why Aeroplane windows are round?

Solve the counting riddle by identifying the number of triangles in the given picture.

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?