Theory:

To prepare pancakes for four people, 3 cups of flour is mixed with 2 cups of milk.
 
Think of how many cups of flour and milk needed to prepare pancakes for \(8\) people!
Think of how many cups of flour and milk needed to prepare pancakes for \(2\) people!
 
The given amount '3 cups of flour is mixed with 2 cups of milk' is for \(4\) people.
 
As we want to prepare for \(8\) people, we have to take double the amount what we took for \(4\) people.
 
So, to prepare pancakes for \(8\) people, we need '6 cups of flour and 2 cups of milk'.
 
Similarly to prepare pancakes for \(2\) people, we have to take half the amount what we took for \(4\) people.
 
So, to prepare pancakes for \(2\) people, we need '1 and half a cups of flour and 1 cup of milk'.
 
In all the cases, the number of cups of flour\(:\) number of cups of milk \(= 3:2\).
 
Here we have to compare the amount of flour and milk used to prepare pancakes.
 
This sort of comparison by expressing one quantity as the number of times the other is called a 'Ratio'.
 
A ratio is a comparison of two quantities. The ratio of the two quantities \(a\) to \(b\) has to be written as \(a:b\).
 
The ratio of two quantities \(a\) and \(b\) are termed as \(a:b\). Where \(a\) is called the first term or antecedent and \(b\) is called the second term or consequent.
 
Any ratio \(a:b\) can be pronounced as \(a\) is to \(b\).
 
It also can be written as \(a\) to \(b\) or \(a/b\).
    Important!
  • A ratio is a comparison of two quantities.
  • A ratio can be written as a fraction.  Usually, the ratio is expressed in the simplest form.