# Overview

## Topics covered in the module

In this module we will study about:

Ratio

Proportion

## How to compare two data values?

What are the tools or methods available to us if we want to compare two numbers?

Let us try to understand it using an example.

Cost of a shoe is Rs. 2500 and cost of a mobile is Rs. 5000.

We can compare two data values of the same type using three methods:

Difference method, (a - b):

Difference = Rs. 2500.Percentage method:

Cost of shoe as a percentage of the cost of mobile = ($\frac{2500}{5000}$) × 100 = 50%Division or Ratio method, (a/b or a:b):

Ratio of the two values = $\frac{2500}{5000}$ = $\frac{1}{2}$

While the Difference method is very elementary, we have already studied the Percentage method in a previous module.

The focus of this module is Ratio and by extension Proportion too.