Top step is 70 cm off the ground and the ramp is to make an angle of 4degrees with the ground,?

From Sin = Opp / Hyp Length of ramp Slope = Hyp = Opp / Sin 4deg = 0.7m / 0 = 10.035m = ANSWER A rise of 0.7m and ramp length of 9m, gives ramp angle = Sin^-1 ( Opp / Hyp) = Sin^-1 ( 0.7 / 9) = 4.46 deg As this angle is less than 4.8 deg and the ramp length does exceed 9m , the adjusted design meets the code = ANSWER Diagrams are simple right-angle triangles. Hope this helps.

From Sin = Opp / Hyp Length of ramp Slope = Hyp = Opp / Sin 4deg = 0.7m / 0 = 10.035m = ANSWER A rise of 0.7m and ramp length of 9m, gives ramp angle = Sin^-1 ( Opp / Hyp) = Sin^-1 ( 0.7 / 9) = 4.46 deg As this angle is less than 4.8 deg and the ramp length does exceed 9m , the adjusted design meets the code = ANSWER Diagrams are simple right-angle triangles. Hope this helps.

If you actually want to know HOW to do trig (rather than just getting the answer to THIS particular problem), here are three tutorials that give you the basics of "right angle" trigonometry. The first shows you how to create a "Trig Tool" (so you don't have to memorize a lot of formulas) and the next two show you how to use it. http://www.ehow.com/how_5520340_memorize-trig-functions-losing-mind.html http://www.ehow.com/how_5227490_pass-mind-part-unknown-sides.html http://www.ehow.com/how_5428511_pass-part-ii-unknown-angles.html Maranatha