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Homework Help: Any ideas ?

  1. Jan 22, 2009 #1
    Any ideas ??

    1. The problem statement, all variables and given/known data

    divide 6705 in the (ratio square r00t sign-2 : square root sign-8).


    3. The attempt at a solution

    I don't know where to begin.
     
  2. jcsd
  3. Jan 22, 2009 #2
    Re: Any ideas ??

    I have no idea what you are asking.
     
  4. Jan 22, 2009 #3
    Re: Any ideas ??

    Basically it has to do with ratios.

    I am asking how would you divide £6705 in the ratio 2:8.

    But both the 2 and 8 have a square root sign each, but i cannot put the sign because my keyboard hasn't got a key with a sign on it.

    It doesn't really make sense to me and thats why i am asking you guys to see if any one can help me.

    Thanks
     
  5. Jan 22, 2009 #4
    Re: Any ideas ??

    Yes but those are still just numbers, you are trying to proportion out 6705, you are told relative weights, so what would the equation be?

    Let's try a simple problem let's say it WAS just 2:8, how would you do it?
     
  6. Jan 22, 2009 #5
    Re: Any ideas ??

    Adding 2 and 8 together and then divide the total amount by the amount i got after i added.

    That would give me the ratio in each unit.
     
  7. Jan 22, 2009 #6
    Re: Any ideas ??

    Right so tell me the final answer, if I told you the relative weights are 2 and 8, how much would go each "bucket"
     
  8. Jan 22, 2009 #7
    Re: Any ideas ??

    2+8=10

    6705 / 10=670.5

    670.5 is the amount of each unit in the ratio, If i multiply 670.5 by 2 i get 1341 and 670.5 multiply by 8 i get 5364.


    Thats all good but my only problem lies with the square root sign if you know what i mean.
     

    Attached Files:

  9. Jan 22, 2009 #8
    Re: Any ideas ??

    The square root should not matter.

    Look at what you did, you had a:b

    So you said amounts in "one" unit is 6705/(a+b).

    Now the amount in the "first bucket" is a*6705/(a+b) and in the "second bucket" it's b*6705/(a+b).

    In the example we just worked, a = 2, b = 8. In your problem, [tex] a = \sqrt{2}, b = \sqrt{8} [/tex]

    Note also that [tex] \sqrt{8} = 2 \sqrt{2} [/tex] so you can simplify your calculations a little bit.
     
  10. Jan 22, 2009 #9
    Re: Any ideas ??

    So when i get the solution, should the square root sign still be there ?
     
  11. Jan 22, 2009 #10
    Re: Any ideas ??

    Nope, show me your work using what I told you.
     
  12. Jan 22, 2009 #11
    Re: Any ideas ??

    i got 2236.3 for A using the formula you gave me.

    I am a little bit confused somewhere.

    Is there any chance you could do part A and show me what you mean.
     
  13. Jan 22, 2009 #12
    Re: Any ideas ??

    Go ahead and show you work like I said in the previous post.
     
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