Pie Charts Concepts

Understanding the Concepts of Pie Charts

A pie chart is a circular graph that visually represents data in proportions. They are divided into sectors or slices. A pie chart requires a list of categorical variables and numerical variables. Here, the term "pie" represents the whole, and the "slices" represent the parts of the whole.

The size of the sector shows the value of the data in terms of percentages, frequencies, or ratios. Since it's based on angles, it's highly useful in displaying proportions or data which add up to a whole. It allows us to know how much is the weightage of each part in the complete dataset.

This makes pie charts a preferable choice to determine percentages or fractions of something. For example, highlighting data about total sales, budget, demographic distribution, choices by people, etc.

To solve pie charts questions effectively, we are supposed to know a few concepts as most of the concepts around finding the sum, averages, percentages, and ratios.

The following are the important pie charts concepts:

1. Speed Maths

Quicker calculation techniques are the key to solving any data interpretation question faster. A quick calculation can be mastered by working on 2 things:

1.1 Memory based

There are a few things we need to know by heart to do the calculations faster, ex - Squares of numbers from 1 to 40, 20 x 20 multiplication table, etc.

For Example:

Squares of numbers from 1 to 40, 20 x 20 multiplication table, cubes of numbers from 1-12, powers of numbers from 2¹ to 2¹², etc.

1.2 Calculation based Shortcuts

Few speed math techniques can be learned to perform calculations faster.

For Example:

2 x 2 multiplication, finding squares of numbers, finding square roots quickly, etc.

2. Averages

There are a few average-based questions asked in most of the pie chart sets, solve this effectively by adding the numbers and dividing them, and quick calculation of averages using approximation techniques will definitely help.

Special Clue: In most of the 'find the angle-based questions', the answer will be a multiple of 9.

3. Percentages

There are specific percentage-based questions asked in most of the pie chart sets, like 'what percentage of A is B', 'A% of B,' or 'percentage change'. To solve this effectively we need to be very good at calculating percentages.

4. Ratios

Some of the questions from the pie chart question sets are based on ratios. These can be easily solved using approximation techniques, divisibility tests, and a basic foundational understanding of ratios. Percentage concepts will also be a great help in solving pie chart question sets.