How many times can you subtract the number 5 from 25?

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?

What number does the below three word/phrase identify and why?
1. Deck
2. Year
3. Singing in the Rain

There was a strange boy who was born before his father. How can this be possible?

Be active and find the killer in the picture Riddle below.

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!

What is the fastest way to double your money?

A man is looking at a photograph of someone. His friend asks who it is. The man replies, “Brothers and sisters, I have none. But that man’s father is my father’s son.” Who was in the photograph?

I have teeth but i don't bite. Who Am I ?

John was a very careless driver, so his owner Jacob gave him an offer that he will get an incentive of Rs.30 for every bottle box he delivered without breaking it and he will be charged Rs.90 for every bottle box he broke. Jacob gave John 100 bottles-box to deliver. After delivery, Jacob paid John Rs.2400. How many bottles-box did John break?