Will someone help me with my math homework?

A drawing of a house and tree is 1/15 of the actual house and tree. The tallest point of the house is 10ft and 3in and the tree is 30ft tall. How many inches is the tree in the drawing?

Please please please help I don't understand this at all. I know it is a proportion right and I understand that 1/15 is like the key that shows you the comparison between the drawing and the actual house and tree but do I convert it or what?