Problema Solution

Highway 195 into Lewiston, Idaho undergoes a difference in elevation of 1800 feet in 7 miles. What is the average percent slope of the Lewiston grade?

Answer provided by our tutors

1 mi = 5280 ft

7 mi = 5280*7 ft

rise = 1800 ft

run^2 = (5280*7)^2 - 1800^2

run = 36,916.14 ft

Percent slope = (rise/run)*100

Percent slope = (1800/36916.14)*100

Percent slope = 4.86%

The average percent slope is 4.86% approximately.