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A 5 to 1 slope is one that, **for every increase of 5 units horizontally, rises by 1 unit**. The number of degrees between a 5 to 1 slope and the x-axis is 11.3°.

For example, a 25 percent slope is simply a **ratio of 25:100**. The 25 percent slope below shows that the slope rises . 25 inches for every inch of horizontal distance. The slope rises 2.5 centimeters or every 10 centimeters of horizontal distance, and it rises 1.25 inches for every 5 inches of horizontal distance.

For example, a **33%** slope may also be described as a “3:1 slope,” meaning the land falls 1 foot for ever 3 foot of distance.

Example: a road with 15% slope has an angle of **8.53°**.

Percent of slope is determined by **dividing the amount of elevation change by the amount of horizontal distance covered** (sometimes referred to as “the rise divided by the run”), and then multiplying the result by 100.

For a ramp the maximum running slope allowed is **8.33%** (8.33% is a 1:12 slope).

Degrees | Gradient | Percent |
---|---|---|

1.19° | 1 : 48 | 2.08% |

2.86° | 1 : 20 | 5% |

4.76° | 1 : 12 | 8.3% |

7.13° | 1 : 8 | 12.5% |

Slope (%) | Approximate degrees | Terminology |
---|---|---|

15 – 30 | 8.5 – 16.5 | Strong slope |

30 – 45 | 16.5 – 24 | Very strong slope |

45 – 70 | 24 – 35 | Extreme slope |

70 – 100 | 35 – 45 | Steep slope |

What is a 1 in 40 fall? A 1 in 40 pipe fall means that **for every 40 units of length, the pipe will drop by 1 unit**. For example, in a 40 metre run of pipe, the vertical drop of that pipe run will be 1 metre.

For example, “slopes are expressed as ratios such as 4:1. This means that for **every 4 units (feet or metres) of horizontal distance there is a 1 unit (foot or metre) vertical change either up or down**.”

To calculate percent slope, divide the difference between the elevations of two points by the distance between them, then multiply the quotient by 100. The difference in elevation between points is called the rise. The distance between the points is called the run. Thus, percent slope equals **(rise / run) x 100**.

One-eighth inch is 1/96 of a foot. That is **1.04% of a foot**.

So what’s a steep grade? **Grades are typically marked when they reach 5% or more**. On the US Interstate Highway system grades are not allowed to be over 6%; on other roads and highways there is no limit. RVers generally agree that the longer the grade the greater the concern.

A 45-degree pitch is equivalent to a **100-percent grade**, and both mean that a run descends one vertical foot for each horizontal foot. “In perspective, a very steep highway-pass road is approximately 7 percent or about 4 degrees,” according to the Highlands Extreme Guide trail map.

1% as a decimal is **0.01** and hence the slope is 0.01. That means for a run of pipe of a certain length the rise must be 0.01 times the length. Thus for you example, since the length of the run is 80 feet which is 80 × 12 = 960 inches the rise must be 0.01 × 960 = 9.6 inches.

A 6% grade refers to the slope of a road, and the percent value means “per one hundred.” At a 6% grade, you **increase your elevation by six units for every 100 units**.

- Subtract starting value minus final value.
- Divide that amount by the absolute value of the starting value.
- Multiply by 100 to get percent decrease.
- If the percentage is negative, it means there was an increase and not an decrease.

**Divide the length of the wheelchair ramp by the height**. This will be the second number in your ratio. The first number is always one. If the ramp measures 12 feet long and the rise is 2 feet, you would divide 12 by 2 to get 6, and your ratio would be 1 to 6.

The slope of a line is the angle at which it rises or falls, and a **ratio is a comparison of values**. Based on this, the slope can be expressed as a ratio. In the case of a line’s slope, the ratio is the “rise” of the line expressed in relation to the “run” of the line.

Angle (°)Percent (%)Ratio (H:V)24.245.026.149.0**26.6****50.0**2:130.057.7

Slope percent is important in figuring how to contour land. A 1/2-percent slope is **used for applications that involve drainage of land and concrete**, such as patios and sidewalks. It also figures significantly in conservation farming irrigation, where the land most vulnerable to rain erosion gets a 1/2-percent slope.

Steep slopes are legally defined as hillsides having a 15 foot, or greater, vertical rise over 100 feet of horizontal run, or **15% slope** (Figure 1). They are often undesirable ar- eas for development due to the difficulty of building on steep grades.

It doesn’t matter exactly what it means, 20% is **steeper than 10%**. In surveying 20% is interpreted as 20% of a right angle (i.e. a brick wall) and so would be 18 degrees.

If **you keep the velocity in the channel below critical flow and velocity is below allowable for the ground cover** then you have a gentle slope. If flows are critical flows or above and the velocity of flow is greater than the allowable for the ground cover then you have a steep slope.

A 60 percent slope corresponds to a slope angle **of 31°**.

Generally, minimum slope for water to run off is **1%** (1/8″ per 1′).

Introduction to Gradients A 1:0.5 slope means that for every 1 metre along the ground, the slope height increases by 0.5 metres. … For instance, a 1:40 gradient number is shown as **0.025** (an example is shown in the calculation section).

**Multiply for a 4 to 1 Slope** **Multiply the pond depth by 4 to find the total length the** pond must extend to achieve a 4:1 slope. If the depth is only 1 foot, for example, the pond must extend 4 feet. A total length of 12 feet is needed if the pond is 3 feet deep.

To find the percent of incline of a grade, **solve the rise/run fraction as a decimal**, then convert to a percentage. For example, if the grade is 5/16, solve as a decimal, which is . 3125. To find the percentage multiply this decimal by 100, like this: 100 × .

In geometry, 1 in 10 means for every ten units of horizontal distance crosses there is 1 unit of vertical drop or rise. The angle of tan is used to measure this value of slope. … Hence, **6 degrees** is the angle of 1 in 10 slope.

The fall and length need to be in the same units (feet or inches) for this to work. For example, if the pipe fell by one foot and was 50 feet long, you divide 1 by 50 to get 0.02. Multiplied by **100**, that becomes 2 percent, which is your slope or gradient.

To the fraction 15 as a percent is **20%** .

- Multiply the number of feet of your pipe (X) by the inches you’re planning to slope the line (Y).
- This will give you the difference in height (Z) between the beginning and end of the pipe: (X) x (Y) = (Z).

The percentage grade is the slope, written as a percent. To calculate the slope you divide the rise by the run. In your example the rise is 80 ft over a run of 3280 ft so the slope is 80/3280 = 0.024. Written as aa percent this is **2.4 %**.

Originally Answered: What is a 15 percent incline on a treadmill? It is **the angle from the horizontal that would result in a 15 m rise for every 100 m horizontal distance**. In other words the angle from the horizontal with a tangent of 0.15.