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Oct 11, 2005, 2:26:32 AM10/11/05

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Hi,

I need help to figure how to do this problem: 10 x 1:12.

My goal actually is to find the height of a ramp where the slope of

each section is 1:12 (what does that mean?) and the base is 10.00 m.

Thank you,

Tone

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Oct 13, 2005, 12:12:19 AM10/13/05

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Slope is "vertical over horizontal". Fore a ramp, it is height over

base. Or it is the ratio of the height over the base. So if the slope

of the ramp is 1:12, that means where the height is 1, the base is 12.

Or, imagine a right triangle. The hypotenuse is the ramp. The vertical

leg is the height, and it is 1m. The horizontal leg is the base, and it

is 12 m.

If the base were 10 m only, what then is the corresponding height on

the ramp?

Imagine again the same right triangle but the horizontal leg is 10m

only. How do you get the height of this smaller right triangle?

One way is by proportion.

(height):(base) = (height):(base)

1:12 = h:10

That is the same as:

1/12 = h/10

Multiply both sides by 10,

10/12 = h

h = 10/12 = 5/6 = 0.8333 m.

Oct 13, 2005, 12:12:20 AM10/13/05

to

hightone <tshivp...@gmail.com> wrote:

: Hi,

: I need help to figure how to do this problem: 10 x 1:12.

: My goal actually is to find the height of a ramp where the slope of

: each section is 1:12 (what does that mean?) and the base is 10.00 m.

"What does that mean?" - No offense, but I think it means you need

to go back to your math teacher and explain that you don't understand

the problem.

A ratio is a fraction, in this case it is dealing with a slope, so

think of it as "rise over run". How far up (or down) does the slope

change over the distance it goes. 1:12 will go up 1 inch for every

12 inches or 1 foot for every 12 feet or 1 mile for every 12 miles.

In your case, it will go up 1 meter for every 12 meters.

10 x 1:12 = 10 x 1/12

--

-davec

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Oct 13, 2005, 12:12:25 AM10/13/05

to

On Tue, 11 Oct 2005 06:26:32 GMT, "hightone" <tshivp...@gmail.com>

wrote:

>

>Hi,

>

>I need help to figure how to do this problem: 10 x 1:12.

>

>My goal actually is to find the height of a ramp where the slope of

>each section is 1:12 (what does that mean?) and the base is 10.00 m.

>

>Thank you,

>Tone

The slope is 1 / 12 which means for every meter along the base it

rises 1 /12 meter. So if its base is 10 meters long it rises....?

--Lynn

Oct 13, 2005, 12:12:27 AM10/13/05

to

hightone wrote:

>

> Hi,

>

> I need help to figure how to do this problem: 10 x 1:12.

>

> My goal actually is to find the height of a ramp where the slope of

> each section is 1:12 (what does that mean?) and the base is 10.00 m.

1:12 --> rise/run --> for every unit in the horizontal direction it

rises 1/12 of that same unit.

So, if the base is 10 instead of 12, the height is 10/12.

Oct 14, 2005, 12:43:53 AM10/14/05

to

Hi,

I want to thank you all that responded to the question. I really

appreciate you taking the time to help me.

Regards,

Tony

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