Results 1 to 5 of 5
Like Tree2Thanks
  • 1 Post By romsek
  • 1 Post By JeffM

Math Help - How to calculate the reference of numbers?

  1. #1
    Newbie
    Joined
    Jul 2014
    From
    NJ
    Posts
    2

    How to calculate the reference of numbers?

    Is there anyway to calculate the following? As you can see when the first number increases the 2nd number only increases a little bit. I would like to calculate the other numbers with the same reference. Thanks

    6.6162 = 2.598
    11.2262 = 2.939

    9.2362 = ? ( I know is around 2.7 something)
    4.9068 = ?
    2.7659 = ?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Nov 2013
    From
    California
    Posts
    2,489
    Thanks
    963

    Re: How to calculate the reference of numbers?

    Quote Originally Posted by leosantare View Post
    Is there anyway to calculate the following? As you can see when the first number increases the 2nd number only increases a little bit. I would like to calculate the other numbers with the same reference. Thanks

    6.6162 = 2.598
    11.2262 = 2.939

    9.2362 = ? ( I know is around 2.7 something)
    4.9068 = ?
    2.7659 = ?
    You can do a linear interplation/extrapolation.

    Just use the point slope formula for a line.

    $m=\dfrac {2.939-2.598}{11.2262-6.6162} \approx 0.074$

    $y-y_0 = m(x-x_0)$

    $(y-2.939) \approx 0.074(x-11.2262)$

    $y\approx 0.074 x +2.1082612$

    $\begin{pmatrix}
    2.7659 &2.313\\
    4.9068 &2.471\\
    6.6162 &2.598\\
    9.2362 &2.792\\
    11.2262 &2.939
    \end{pmatrix}$
    Thanks from topsquark
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Super Member
    Joined
    Feb 2014
    From
    United States
    Posts
    568
    Thanks
    274

    Re: How to calculate the reference of numbers?

    Quote Originally Posted by leosantare View Post
    Is there anyway to calculate the following? As you can see when the first number increases the 2nd number only increases a little bit. I would like to calculate the other numbers with the same reference. Thanks

    6.6162 = 2.598
    11.2262 = 2.939

    9.2362 = ? ( I know is around 2.7 something)
    4.9068 = ?
    2.7659 = ?
    Unfortunately, there are an infinite number of possibly correct answers. If you had more data, you could exclude many possibilities, but no matter how much data you had, you could never be 100% certain of getting the correct answer.

    With this little in the way of data, your best guess is to assume a linear relationship.

    $\dfrac{y - 2.939}{x - 11.2262} = \dfrac{2.939 - 2.598}{11.2262 - 6.6162} = \dfrac{0.341}{4.61} \implies 4.61y - 13.54879 = 0.341x - 3.8281342 \implies$

    $y = \dfrac{0.341x + 13.54879 - 3.8281342}{4.61} = 0.074x + 2.1086.$

    Let's check

    $0.074 * 6.6162 + 2.1086 \approx 2.598.$ Looks good.

    $0.074 * 11.2262 + 2.1086 \approx 2.939.$ Looks good.

    So for example $0.074 * 9.2362 + 2.1086 \approx 2.792.$
    Thanks from topsquark
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Newbie
    Joined
    Jul 2014
    From
    NJ
    Posts
    2

    Re: How to calculate the reference of numbers?

    Wow, that's pretty cool. These equations are much more advanced to me, is this Trigonometry? Although the 2.7659 and 4.9068 are a bit too high. If I provide the smallest and middle values, can you find the relationship of the others more accurately? I'm trying to decide on the number of holes I want on 5 gaskets. The first value represents the bolt hole circle and the second value represents the spacing between the holes, including the curve. I want the spacing to increase slightly in uniform as the bolt hole circle increases in size.

    2.7659 = 2.172 @4 holes
    4.9068 = ?
    6.6162 = 2.598 @8 holes
    9.2362 = ?
    11.2262 = ?
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Super Member
    Joined
    Feb 2014
    From
    United States
    Posts
    568
    Thanks
    274

    Re: How to calculate the reference of numbers?

    I used only elementary algebra. However, you mention curves, and the answers supplied so far do not apply to a curve.

    Someone may be able to help you with respect to a well-defined curve. However, you will have to describe very carefully what kind of curve you are contemplating. This may take time because math has a very precise vocabulary that most people do not know. So there are significant problems in terms of communication.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 1
    Last Post: November 5th 2012, 10:11 PM
  2. Calculate the sum of incrementing numbers...
    Posted in the Algebra Forum
    Replies: 2
    Last Post: August 27th 2010, 02:42 AM
  3. I know how to calculate reference angles but...
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: March 30th 2009, 05:42 PM
  4. Reference Angles...
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: August 15th 2008, 11:56 PM
  5. Reference angle
    Posted in the Trigonometry Forum
    Replies: 3
    Last Post: March 30th 2007, 06:14 PM

Search Tags


/mathhelpforum @mathhelpforum