math 156
posted by Rmz .
if a sewer line drops 1 foot every 40 feet how many feet will drop over a distance of 100 feet?
is it 400 feet?

Think about it.
The line drops
1 foot for every 40 feet
2 feet for every 80 feet
3 feet for every 120 feet
100 / 40 = 2.5