1 percent of a foot is 0,3048 cm.
one hundredth of a foot.
1 foot
2% grade is equal to a 1/4" per foot fall
Drop per foot doesn't care about length of run, it depends on pipe size. Pipe larger than 2" needs only 1/8" per foot (37.5" fall for 300'), 2" and smaller needs 1/4" per foot (75" fall for 300')
Since 9 out of 12 equals 75 percent, then 9 inches out of 12 inches (a foot) is 75 percent.
1.992 INCHES
Half of a foot, which is equal to 6 inches
Use a level which is at least a foot long. Hold the level in the horizontal level position, and measure the 1/4" drop from the position of the level which is one foot from the end. If you have a four foot level, and the space to use it, you can easily measure one inch of drop per four feet, which is the same as 1/4" per foot.
1/8 inch per foot
1 foot = 1 foot.
There is 0.3048 meters in 1 foot