The 2008 Level 3 Specification for Skills says: Candidates will be required to calculate slope angle from a topographic map and provide an answer in degrees and percent.

1. An angle in degrees ° 2. A percentage % Learning how to calculate slope angle (gradient) as a degree and as a percentage before going into the 2008 exam would be wise also make sure you have a scientific calculator.

Two pieces of information are needed to work out degrees: 1. The HORIZONTAL DISTANCE between two points on a map (expressed in metres) 2. The DIFFERENCE IN HEIGHT between the lowest point and the highest point (expressed in metres) Note: The horizontal distance and height need to be expressed in the same unit of measurement The slope angle will be an average over the distance, it will not take into consideration valleys or peaks across that distance Working out slope in degrees is simple by following five easy steps

200m 150m 100m 250m 300m 325m Scale: 1: (1cm = 500m) A B

difference in height (m) horizontal distance (m) Slope = 225m 225m1500m = 0.15 (gives a decimal answer) = 0.15 = Tan¯¹ 0.15 = 8.5 = 8.5 ° (1dp) ° degrees is the angle of slope

Simply go back to the decimal answer (step 4) and convert to a percentage... o.15 x 100 = 15% The slope angle as a percentage is 15% So that is a gradient of 8.5 as a degree or a gradient of 15% as a percentage So that is a gradient of 8.5 ° as a degree or a gradient of 15% as a percentage

accessed 9/6/08 H. McMillan - Saint Kentigern College Martin Newton Nick Page - Otumoetai College