Chapter Overview

Data Interpretation (आँकड़ों की व्याख्या) is where CGPSC Prelims Paper II (CSAT) puts your arithmetic to work. Instead of a word problem, you get a table, a bar or line graph, or a pie chart, followed by a set of questions on it: which value grew fastest, what share one item holds, what the average was. Data Sufficiency (आँकड़ों की पर्याप्तता) flips the task: you are not asked for the answer, only whether the statements given are enough to find it.

The CGPSC syllabus lists “data interpretation (charts, graphs, tables, data sufficiency etc.)” at Class X level — so the mathematics is only percentages, ratios and averages. What separates a good score from a poor one is reading the data correctly and calculating with approximation instead of long division.

All data in this chapter is hypothetical

Every table, graph and pie chart in these notes uses made-up practice figures (districts are labelled A, B, C …; schemes and societies are imaginary). They are designed to produce clean numbers for learning, not to describe real Chhattisgarh or India statistics. Do not quote them as facts in Paper I or Mains.

What You’ll Learn

By the end of this chapter, you’ll be able to:

Read a table row-wise, column-wise and as a whole, and answer total, share, growth and ratio questions on it
Tell apart absolute change and percentage change on bar and line graphs, and read growth from a line’s slope
Convert pie-chart degrees to percentages and amounts in one step, and compare two pie charts with different totals
Use the five standard answer choices of data sufficiency and decide sufficiency without solving fully
Approximate fast enough to finish a 5-question DI set in about 5 minutes

Prerequisites

Before starting this chapter, you should be comfortable with:

Percentages — percentage change, percentage points, successive change
Ratio and Proportion — comparing and dividing quantities
Averages — sum = average \( \times \) count, weighted averages

Learning Path

Follow these topics in order — each builds on the one before:

graph TD
    N[Basic Numeracy: %, ratio, average] --> A[1. Tables]
    A --> B[2. Bar and Line Graphs]
    B --> C[3. Pie Charts]
    C --> D[4. Data Sufficiency]
    D --> Q[Quick Revision sheet]
    D -.-> L[Logical Reasoning]

Topics in This Chapter

Topic	Description	Time
Tables	Row/column reading, totals, shares, growth, ratios and averages; approximation and fraction comparison	12 min
Bar and Line Graphs	Simple, grouped and stacked bars; line graphs, slope vs percentage growth, two-line gaps	12 min
Pie Charts	Degrees \( \leftrightarrow \) percent \( \leftrightarrow \) amount, comparing two pies with different totals	10 min
Data Sufficiency	The five standard answer choices, “Is” vs “What” questions, traps with negatives and hidden data	12 min
Quick Revision	Every conversion, formula and trap from the chapter on one page	5 min

Where It Is Asked

Paper	How it appears
Prelims Paper II (CSAT)	Objective MCQs on tables, charts, graphs and data sufficiency at Class X level, within the 100-question, 200-mark, 2-hour aptitude paper. DI usually comes as a set — one dataset, several questions.

Paper II is qualifying — DI is a dependable scorer

Paper II marks are not added to your merit, but you must cross the minimum qualifying mark — commonly cited as 33%; confirm the threshold in the current CGPSC notification. Wrong answers carry negative marking of one-third of the question’s marks. A DI set is a good place to bank marks: once you have read the dataset, every question on it is quick, and the answers are exact.

The skills overlap with other CSAT chapters: Logical Reasoning and General Mental Ability use the same “is the information enough?” thinking as data sufficiency, and Decision Making often rests on reading a small table. In Paper I and Mains, the same habit — reading a table from the Economic Survey without misreading the base year or units — helps in Economy: Basic Concepts and Chhattisgarh Economy and Schemes.

Quick Reference

Key Formulas

Concept	Formula
Percentage change	\( \frac{\text{New} - \text{Old}}{\text{Old}}\times 100 \)
Share of an item	\( \frac{\text{Item}}{\text{Total}}\times 100 \)
Pie: degrees to percent	\( \text{Percent} = \frac{\text{Degrees}}{3.6} \)
Pie: percent to degrees	\( \text{Degrees} = \text{Percent}\times 3.6 \)
Pie: degrees to amount	\( \frac{\text{Degrees}}{360}\times \text{Total} \)
Average of a row/column	\( \frac{\text{Sum}}{\text{Count}} \)
Percentage point change	New % \( - \) Old %

Data sufficiency answer choices (standard pattern)

Choice	Meaning
I alone	Statement I alone answers; II alone does not
II alone	Statement II alone answers; I alone does not
Either	Each statement alone answers
Both	Neither alone, but I and II together answer
Neither	Even together they do not answer

Exam Focus

High-yield: highest/lowest percentage growth, share of total, ratio of two values, average over years, pie-degree conversions, “both together” DS questions.
Favourite traps: largest absolute rise vs largest percentage rise; falling share with rising amount; percent vs percentage points; a negative number hiding in an “Is” question.
Speed target: read the dataset once (about 60 seconds), then under 60 seconds per question.

Start Learning

Ready to begin? Start with the first topic:

→ Tables