Results 1 to 7 of 7

Thread: Hi Everyone, I知 a sports coach who needs help with a calculation in a spreadsheet!

  1. #1
    Newbie
    Joined
    Oct 2017
    From
    Yorkshire
    Posts
    3

    Hi Everyone, I知 a sports coach who needs help with a calculation in a spreadsheet!

    Firstly let me apologise for my lack of maths skills!! I work as a sports coach and I知 very adept at the day to day calculations I need but I知 building a spreadsheet and have hit a problem.

    Basically I need to calculate how many times a number has to be doubled to match a larger number. For example 250 meters (0.25km) has to be doubled twice to match 1km. Ideally I need to calculate this with numbers that don稚 really fit.

    For example 0.4km into 1km!!?? Or 1km into 5km??

    Any help would be appreciated and sorry if this is super simple as so am!

    Morgan
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    Joined
    Jun 2013
    From
    Lebanon
    Posts
    742
    Thanks
    341

    Re: Hi Everyone, I知 a sports coach who needs help with a calculation in a spreadshee

    use logarithm base 2. A spreadsheet program has this functionality built in.

    so, for example, from 0.25 to 1km , we would first divide

    \frac{\text{target}}{\text{initial}}=\frac{1}{0.25  }=4

    then \log (4,2)=2 therefore we must double twice to hit the target

    another example, 1 to 5km, divide to get 5 and then \log (5,2)=2.32

    therefore doubling twice is under target and doubling three times is over target
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor
    Joined
    Feb 2015
    From
    Ottawa Ontario
    Posts
    1,695
    Thanks
    318

    Re: Hi Everyone, I知 a sports coach who needs help with a calculation in a spreadshee

    10 : 1000
    10 + 20 + 40 + 80 + 160 + 320 + 640 = 1270

    a = initial number (10)
    t = target number (1000)
    n = number of doublings (?)
    Formula:
    n = log(t/a + 1) / log(2) - 1
    n = 5.658...

    z'dat clear nuff Morgan?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Newbie
    Joined
    Oct 2017
    From
    Yorkshire
    Posts
    3

    Re: Hi Everyone, I知 a sports coach who needs help with a calculation in a spreadshee

    Thanks folks!! I'll give this a whirl but no doubt I'll be back with another question!
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    11,071
    Thanks
    708
    Awards
    1

    Re: Hi Everyone, I知 a sports coach who needs help with a calculation in a spreadshee

    Are you having problems using the spreadsheet or just the math?

    -Dan
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Newbie
    Joined
    Oct 2017
    From
    Yorkshire
    Posts
    3

    Re: Hi Everyone, I知 a sports coach who needs help with a calculation in a spreadshee

    Just the maths, pretty ok with spreadsheets but any thoughts/advice would be appreciated
    Follow Math Help Forum on Facebook and Google+

  7. #7
    SGS
    SGS is offline
    Junior Member
    Joined
    Mar 2015
    From
    Clarion, PA
    Posts
    31
    Thanks
    6

    Re: Hi Everyone, I知 a sports coach who needs help with a calculation in a spreadshee

    Why do you need to calculate this with numbers that don稚 really fit? There are going to be more times
    numbers that don稚 really fit.

    In your first example, 250 meters (0.25km) has to be doubled twice to match 1km so the answer you should get in your spreadsheet should be 2. In your second example. 0.4km into 1km the answer you should get is "more than once". What does the different types of answers mean to you when you see them in your spreadsheet?

    Steve
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Math Coach
    Posted in the Algebra Forum
    Replies: 1
    Last Post: Apr 19th 2011, 02:50 PM
  2. Help w/ Excel spreadsheet & probability
    Posted in the Statistics Forum
    Replies: 1
    Last Post: May 19th 2010, 10:51 PM
  3. Spreadsheet equations
    Posted in the Advanced Algebra Forum
    Replies: 1
    Last Post: Mar 2nd 2010, 09:30 AM
  4. Need Blackjack Spreadsheet
    Posted in the Advanced Statistics Forum
    Replies: 0
    Last Post: Jan 27th 2010, 04:49 PM
  5. Spreadsheet help
    Posted in the Pre-Calculus Forum
    Replies: 0
    Last Post: Oct 28th 2008, 05:37 PM

/mathhelpforum @mathhelpforum