# Average Grade

### From FIS Freestyle wiki

** Average Grade** This is the average

**slope**gradient (in percent) of the terrain under the length of the ski lift, from top terminal to

**bottom terminal**.

Calculate slopes one must have some understanding of it.

**Slope**, **tilt** or **inclination** can be expressed in three ways:

- As a ratio of the rise to the run (for example 1 in 20)
- As an angle (almost always in degrees)
- As a percentage called the "grade" which is the (rise ÷ run) * 100.

Of these 3 ways, slope is expressed as a ratio or a grade much more often than an actual angle and here's the reason why.

Stating a ratio such as 1 in 20 tells you immediately that for every 20 horizontal units traveled, your altitude increases 1 unit.

Stating this as a percentage, whatever horizontal distance you travel, your altitude increases by 5% of that distance.

- grade = (rise ÷ run) * 100
- grade = (rise ÷ slope length) * 100

## Reference

- 1728 Software Systems
*Slope of a Road or the "Pitch*of a Roof[1]

Return to **Ski lift**, **Ski Related Definitions**, **Freestyle Equipment Rules**, **General Definitions** or **Freestyle Skiing**