Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

How many times in a given day, minutes and hour clock comes in a straight line ?

What is the fastest way to double your money?

You have two buckets - one holds exactly 5 gallons and the other 3 gallons. How can you measure 4 gallons of water into the 5 gallon bucket?

(Assume you have an unlimited supply of water and that there are no measurement markings of any kind on the buckets.)

My location can be determined by the below rebus.
So where am i ?

An express train takes 3 seconds to enter the tunnel which is 1 km long.
If it is travelling at 120 km an hour, how long will it take to pass completely through the tunnel?

Two in a corner, one in a room, zero in a house, but one in a shelter. What am I?

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

There are seven sisters in a house in a village where there is no electricity or any gadget.

Sister-1: Reading Novel
Sister-2: Cooking
Sister-3: Playing Chess
Sister-4: Playing Sudoku
Sister-5: Washing clothes
Sister-6: Gardening

what is Sister-7 doing ?

This is a picture puzzle. You have to guess the name of the movie that can be related to the picture.