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## Slope on the Manitou Incline, huh?

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### Slope on the Manitou Incline, huh?

I'm missing something...in a big way.

The Manitou Incline has an average grade of 41% and a max of 68% (http://www.inclineclub.com/incline/), doesn't that calculate out to: an average slope of 36.9 degrees and a max slope of 61.2 degrees?

Yet I think everyone would agree that the Incline is nothing close to that and is merely a (quad and lung busting) class 2 hike. So, what am I missing here?

Am I thinking of % grade wrong?
Isn't 100% grade, vertical and 90 degrees, vertical? And therefore: (percent grade/100) X 90 degrees = slope in degrees?
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### Re: Slope on the Manitou Incline, huh?

Isn't 100% grade, vertical and 90 degrees, vertical? And therefore: (percent grade/100) X 90 degrees = slope in degrees?

No, precent of grade is rise to run or amount of vertical gain over a given distance. Therefore 100% grade is 100' of vertical to 100' of horizonal. 100' / 100' * 100 = 100%. 100% grade is 45 degrees. At 41% that about 22.29 degrees. and 67% is 33.82 degrees.
Last edited by JayMiller on Thu Aug 07, 2008 2:41 pm, edited 1 time in total.
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### Re: Slope on the Manitou Incline, huh?

You have to take the arc tangent of the decimal format of the grade to get the degree slope.
0Â° 0%
10Â° 18%
20Â° 36%
30Â° 58%
40Â° 84%
45Â° 100%
50Â° 119%
60Â° 173%
70Â° 275%

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### Re: Slope on the Manitou Incline, huh?

Your math is wrong, as you might have guessed.

The grade is the amount of "up" you have compared to the amount of "forward" you have. A grade of 41% says that for every 100ft. forward, you go up 41ft.

If you bring out your trig from high school, you'll know that you have to take the atan of the grade percentage to get the degrees. So a 68% grade is a 34.2 degree angle.

Vertical would be an infinite grade. A grade of 100% would be 45 degrees.

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### Re: Slope on the Manitou Incline, huh?

41% = 20.3 degrees
68% = 34.2 degrees

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### Re: Slope on the Manitou Incline, huh?

Here's a web site that takes all of the effort out.

http://www.csgnetwork.com/righttricalc.html
My Philosophy on Life: If you wake up alive and well ... Shut the heck up.

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### Re: Slope on the Manitou Incline, huh?

Wow...does everyone know this but me?
(believe it or not, I was a math major in college)

Thanks everyone...I feel infinitely smarter now
"If you're flammable and have legs, you are never blocking a fire exit."
- Mitch Hedberg

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### Re: Slope on the Manitou Incline, huh?

If you simply get more precise with the measurements I'm sure you could honestly report that the incline is dead vertical or perhaps even slightly overhanging at its steepest portion. Measure the downhill-facing side of one of the ties...

Or better yet, measure the curvature of the uphill inside of one of the cut-open drainage pipes that run across it. Then you could even say it is severely overhanging...

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