time required to study car driving

It will take a min of 20 hrs..

You should allow at least 30 hours of driving instruction and practice before you attempt your test. Learning to handle the controls of the car may take you an hour or so but learning to drive safely and to react appropriately in a wide variety of situations takes a lot longer. There is a great deal of theory to learn, too, since you must know the meanings of all the signs and signals and also be aware of the basics of traffic laws. See this short article by a driving instructor: http://www.yell.com/motoring/blog/taking-the-time-how-quickly-will-i-learn-to-drive/