Posted by **anna** on Monday, March 10, 2008 at 8:51pm.

The grade of a road is 7%. What angle does the road make with the horizontal?

I'm confused!! What is the grade of a road? Thanks for the help!

- geometrey -
**drwls**, Monday, March 10, 2008 at 8:58pm
The "grade" is the tangent of the slope angle.

arctan 0.07 = 4.00 degrees

(4 degrees is the angle whose tangent is 0.07)

- geometrey -
**drwls**, Monday, March 10, 2008 at 9:05pm
I used the arctan key of my hand calculator. If you don't have one, you should use a table of trig functions

- geometrey -
**drwls**, Tuesday, March 11, 2008 at 8:29am
The answer to your second question is the tangent of 8 degrees. That is 0.1405, for a 14.05% grade.

You don't find many roads that steep. Driveways, maybe.

## Answer This Question

## Related Questions

- Geometry - A road has a grade of 28.4%. This means that the road rises 28.4 ft ...
- geometry - A road climbs at an 8 degree angle with the horizontal. What is the ...
- Geometry - A road climbs at an 8 degree angle with the horizontal. What is the ...
- Pre-Calculus - 74. Road Grade When driving down a mountain road, you notice ...
- Physics - A car with a mass of 900 kg moves along a road at a 89 km/hour at ...
- trig - A road has a 10% grade (slope). To the nearest degree what is the angle ...
- math - the grade of a road is its slope given as a percent. for example, a road ...
- trig - A road has a 10% grade (slope). To the nearest degree what is the angle ...
- Pre-Calculus-Trig - A road rises 140 feet per horizontal mile. What angle does ...
- SLOPE MATH - The grade of a road is its slope given as a percent. for example, a...

More Related Questions