model railway gradients

How can I work on the score needed to lift a 7-inch model train?
I would like to make a record of my start-In miniature, 6 inches. How to develop the best gradient. Thank you. Col Paton
and can be used to cross the dispute to multiply. Cars consume 6 percent and railways from 2 to 4 maximum, is the size and convert it to scale. First convert inches engineers foot, 7 inch equals 0.58 meters to make things simpler. For 2 is 100, and is 0.58 x, to solve X. 2x = 58 x = 29 m
Testing 00 Gradients for model railway