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Comparison between 2 or more quantities

  1. Apr 13, 2008 #1
    Hi everyone, I need your help badly.

    This may sound simple to everyone but I need to get the concept sorted out.

    For ratios, we know that it is a comparison between 2 or more quantities with the same units.

    My question is, can ratio be used to compare between say ingredients in a recipe? say 1 cake needs 5 eggs, 2 cakes needs 10 eggs. Thus 1:5 and 2:10.

    Tecnically they are of different "units" (cakes to eggs) but it seems fine to me if we compare it in such manner.

    Please help me to solve this problem. Thanks.
  2. jcsd
  3. Apr 13, 2008 #2


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    Yes, that is true

    Yes you can I believe.

    You aren't comparing cakes to eggs in the sense that you are taking a cake and dividing it by 5 eggs.

    You are comparing the Number of cakes to the number of eggs.
    So the ratio of the number of cakes you can make to the number of eggs needed to make the cakes is given by 1:5
  4. Apr 13, 2008 #3


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    Yes, you compare two numbers AND units using a ratio. The units of one number go together, and the units of the other number go together. Most of the time, numbers COUNT something. This means a unit goes with a number. A very accessible example generally is fuel efficiency and fuel price. Each of those is a different ratio. The number of miles per gallon is a ratio. That be two numbers. The number of dollars per gallon is another ratio, again two numbers.
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