Two Ropes

Now I am going to give you a simple question that will force you to think and come up with a solution.This has an simple argument.

There are two piece of rope. Ropes are not uniform when consider the cross section and materiel. Also ropes are different from each one. When we burn two ropes respectively it takes one hour to burn completely each one. How we measure 45 minutes from these two ropes by burning?

This is my first post on blogger. So if there is any inconvenience with language please comment....thanks your participation....:) I heard this from adeesha