Theory:

The ratio compares two or more things of the same kind.
In other words, the relations in which one quantity bears with respect to the other quantity of the same kind is called ratio.
 
It is represented as '\(:\)' read as 'is to'.
 
That is \(a : b\) which means \(a\) is the part of \(b\). Here '\(a\)' is called antecedent (first term) and '\(b\)' is called the consequent.
Example:
To find the ratio of \(₹\)100 to \(₹\)200.
 
We write this as \(₹\)100 and \(₹\)200 as in the ratio format.
 
That is 100\(:\)200.
 
We can also write the ratio as a fraction and vice versa.
 
That is 100\(:\)200 can also be written as 100:200=100200=12=1:2