Below, you will find the mathematical proof that 10 equals 9.99999?. But is that possible or there is something wrong about it? Can you find the error?

x = 9.999999...
10x = 99.999999...
10x - x = 90
9x = 90
x = 10

John and Jill are madly in love with each other. To remind Jill of his pure love, John wants to send her a ring by post but in their country where burglary is quite prominent, any package that is not locked comes under the risk of being stolen for the contents.

John and Jill possess many padlocks but neither one of them has the other key.

Can you find a way John can send the ring to Jill safely?

What four weights can be used to balance from 1 to 30 pounds?

They are the five precious gems of an everyday sort and all can be found on a Tennis Court. Who are they?

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

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

Name one eight-letter word with 'kst' in the middle, 'in' the beginning, 'and' at the end.?

A new Engineering building containing 100 offices had just been completed. John was hired to paint the numbers 1 to 100 on the doors. How many times will John have to paint the number nine (9)?

There are two words one resembles the "state of rest" and the other is related to "writing/reading material".

Can you name these two words which also sound similar?

What comes
Once in a Year
Twice in a Month
4 times in a Week
6 times in a Day