vertical transition

[Sumpter250]

Percentage = rise, in inches Divided by the run, in inches, multiplied by 100.

A 3" rise in 48" run is, 0.0625, multiplied by 100 is 6.25 percent. Or h / l X100 = percentage of grade where h = the height,
l = the distance over which that height is reached.
The vertical transition: is the percentage ( in this case, 6.25/100= .0625 ) times the horizontal distance ( run ) 48" which equals 3".

Given the percentage, and the desired rise, it would be:
the desired rise, divided by the decimal equivalent of the percentage, in this example: 6.25% divided by 100 = .0625 ( the decimal equivalent of 6.25% )
3" (the desired rise) the run is 3/.0625 = 48"
A desired rise of 5", at 6.25% would be 5/.0625= 80" ( 6'-7.25" ) run
A desired rise of 5", at 4% would be 5/.04 =125" ( 10'-5" ) run
Hope that helps
Pete

:o Why do I have to learn all this "math"? I'll never use it in real life!!!!