If eleven plus two equals one, what does nine plus five equal?

Can you make a six-letter word using the letters N, A and B ?

John was born on March 5, 1970, in Delhi, India. Jacob was born 25 days before John. The year when they took birth, Republic Day fell on Monday.

Can you find out on what day was Jacob born?

In the given figure, you can see that four match sticks are used to form a square. Can you form five squares by using six matches?

I am an eight letter word and I am a computer terminology.
The second, third and fourth letters make an animal.
The fourth, fifth, sixth, seventh and eighth letters make a weapon.
The first, second, third and fourth letters can be taken as an outcome of any exam.
The fifth, sixth, seventh and eighth letter combine to form a high end typing software.

Can you tell who am I ?

In 1990, a person is 15 years old. In 1995, that same person is 10 years old. How can this be?

John was drowned by he was not wet. How?

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)?

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

10+10 and 11+11 can give you the same answer.

Explain how?