calculating "rise" or "run" without a trigonometry calculator - and is TRIG even required?

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    Theodore Diamond

    Jonathan,

    This one is annoying because it's more basic than you expect. Slope =rise/ run. Rise=slope*run. So for your first example, 50'*.025=1.25'. For your second example, 1.5'/80'=.01875=1.875%. There must be a point where you need the trig calculator, but this isn't it.

     

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    Jonathan Chertok (Edited )

    yeah. thanks man. i sort of looked at the trig calculator and then in the exam i saw this and brain locked half way through. if it was presented in inches somewhere presumably you would just convert to what was required in the answer. ...
    ok. it’s coming to me now. i guess i sometimes write 1/100 for 1% or 2.5/100 for 2.5% instead of 0.01 or 0.025 and at some point it started to look weird to me. i guess i got it right.
    so. trig would be for s luminous flux (or whatever) problem? or anything else i wonder?
    ok. thanks it’s /great/ to put that to /bed/...

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    Jonathan Chertok (Edited )

    hey theodore
    one more one here please?
    i think i got to cross multiplying and saw the % symbol in my triangle sketch and thought trig calculator for some dumb reason.
    anyway - can i use SOHCATOA if i wanted to find the hypotenuse in this case? i mean in the instance above that would be:
    Cos 2.5 = 50’/hypotenuse in which case i would need to use the trig calculator? rearrange it and hyp = 50’/Cos 2.5 and just run Cos 2.5 to get the value?
    i mean by definition i can’t use slope for the hypotenuse basically? sort of more complicated than i would expect in some ways...

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    Theodore Diamond

    Doesn't SOHCAHTOA require or give an angle?  I don't think it would work.

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    Jonathan Chertok

    sohcahtoa can give an angle or the length of any leg. i didn’t want to use the calculator and reviewed it quickly.
    then somehow on the exam i got mixed up seeing “1/100” in my slope = rose/run calculations thinking i was doing a this is to this as this is to that cross multiplication (forget what this is called).
    anyway - sort of an obtuse thread but it could be cool to know you don’t (or do) have to use the trig function on the calculator. or that you can or can’t use sohcahtoa (which i find easier)...
    THANKS for the help...

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    Jonathan Chertok

    OK. thought about this one a bit.

    slope = rise / run (and its iterations) is good for deriving any leg of triangle percent slope or any rise or run for a RIGHT TRIANGLE given two of the others.

    SOHCAHTOA is good for the same for any right triangle or any other triangle in a similar manner. it requires the derivation of SIN degree, COS degree or TAN degree using a calculator.

    what type of question or whether it is necessary to use the calculator on this exam would be helpful to know. also, if it is required it could be helpful for others if someone posted up how one uses this function on the implementation of the calculator. i tried, think i got it but it would be good to have someone post this for others.

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    William May

    I'm confused with this situation.

    If there is a ramp that is to be 50' long with a 2.5% slope would that be 600"x2.5%=15".

    What am I not doing right?

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    Jonathan Chertok (Edited )

    it's a good question. nice to have a practical example posted. there will be other ways to do this but it looks like you have it correct. not sure how to correct the rotation on the forum
     

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    William May

    So, are we not allowed to use a calculator supplied on the test computer?

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    Jonathan Chertok

    have you taken / are you taking these exams?

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    William May

    Can't afford it presently.  And I need more time to study and finding full time work.  We wiped out savings when we put both of my parents in nursing homes and haven't been able to find long term work.  Oh well.  Such is life.

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    Theodore Diamond

    William,
    You can practice on the test software at NCARB'S website. A lot of people ignore this and get really tripped up. I don't know of any practice material that matches it.

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    William May

    Thanks Theodore.  Does that mean a calculator IS provided in the computer we would use?

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    Theodore Diamond

    William, yes. There is a calculator. It's works, but isn't super convenient.

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