Question 44207
20% grade means the height of the ramp is 20% of the ramps horizontal length.
Let H=height and L=length of ramp.
H=0.2L
rearranging gives:
L= H/0.2 = 5H
L= 5 x 11 = 55
So  the length of the horizontal run must be 55ft.



I hope this helps.
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