Study Material — 7 PYQs (2018–2018) · Concept Notes · Shortcuts
RRB NTPC Mixed DI (2-graph sets) is a frequently tested subtopic — 7 previous year questions from 2018–2018 papers are included below with concept notes, key rules and shortcut tricks.
RRB NTPC Mixed DI (2-graph sets) — Past Exam Questions
7 questions from actual RRB NTPC papers · all shown free · click option to reveal solution
Exam Q 12018Previous Year Pattern
If the number of returns (in thousands) equals Customer Count × Return Rate / 100, which category has the highest number of returns?
Exam Q 22018Previous Year Pattern
Which product category has the highest ratio of total customers to return rate?
Exam Q 32018Previous Year Pattern
By what percentage did Electronics sales increase from January to March 2024?
Exam Q 42018Previous Year Pattern
What is the total sales (in ₹ Lakhs) across all four categories for February 2024?
Exam Q 52018Previous Year Pattern
Which company had the highest average quarterly sales across all four quarters?
Exam Q 62018Previous Year Pattern
What is the average employee growth rate from Q1 to Q4 across all five companies?
Exam Q 72018Previous Year Pattern
What is the percentage increase in total sales of Delta from Q1 to Q4?
Concept Notes
Mixed DI (2-graph sets)— Rules & Concept
Core ConceptRead this first — the foundation of the topic
Core Concept
Mixed DI tests your ability to extract information from multiple visual formats and combine them to solve complex problems. Questions often require data from both graphs to reach the answer
Key Rules
Always read both graph titles and legends carefully. Identify what each axis represents. Note the units and scales used. Check if data represents absolute numbers, percentages, or ratios.
Look for common elements between both graphs like time periods, categories, or subjects.
Exam PatternsWhat examiners ask — read before attempting PYQs
SSC CGL typically asks 5 questions per set. Common question types include percentage calculations across graphs, ratio comparisons, finding averages, calculating differences, and trend analysis. Questions may ask for data from one graph only, but often require combining information from both.
ShortcutsUse these to save 30–60 seconds per question
Scan Method
Quickly scan both graphs to understand the relationship between them before reading questions
2
Unit Conversion Trick
When graphs have different units (thousands vs lakhs), convert to same unit immediately to avoid calculation errors
Worked ExampleSolve this step-by-step before moving on
1
Step 1
Extract production data for 2019 from Bar Chart = 60 thousand cars
2
Step 2
Extract export percentage for 2019 from Line Graph = 30%
Convert to required unit = 18 thousand cars
Answer: 18,000 cars or 18 thousand cars
Exam TrapsCommon mistakes students make — avoid these
Students often use data from wrong years, mix up absolute numbers with percentages, forget unit conversions, or use data from only one graph when both are required. Another frequent error is misreading scales or legends, especially when graphs use different scales.
Time Management: Spend 30 seconds understanding both graphs, then 90 seconds per question. Don't get stuck on complex calculations - use approximation when answer choices are far apart.
Key Points to Remember
Mixed DI combines two different graph types with related data themes
Always identify the relationship between both graphs before attempting questions
Check units and scales carefully - graphs may use different measurement units
Most questions require data from both graphs, not just one
Convert percentages to absolute numbers using: (Percentage × Total)/100
Read graph legends and axis labels completely to avoid misinterpretation
Use approximation when answer choices have significant gaps between them
Allocate 8-9 minutes total for 5 questions in mixed DI sets
Exam-Specific Tips
Mixed DI typically contributes 5 questions worth 10 marks in SSC CGL Tier-II
Bar Chart + Line Graph combination appears in 60% of mixed DI questions
Questions involving percentage calculations comprise 40% of mixed DI problems
Ratio and proportion questions account for 25% of mixed DI question types
Time period analysis questions appear in 80% of mixed DI sets
Average calculation questions feature in 30% of mixed DI problem sets
Unit conversion errors cause 35% of wrong answers in mixed DI sections
Practice MCQs
Mixed DI (2-graph sets) — Practice Questions
20graded MCQs · easy to hard · full solution & trap analysis
In which month was the total sales revenue (all products combined) the highest?
Practice 2easy
By what percentage did Laptop sales revenue increase from January to June?
Practice 3easy
What is the total sales (in ₹ thousands) of Mobiles for the months of January to March?
Practice 4easy
What is the average price per unit (in ₹) of Tablets sold in March?
Practice 5easy
In which month was the total sales (all products combined) maximum?
Practice 6easy
What is the total sales revenue (in ₹ Lakhs) for Mobiles across all six months?
Practice 7medium
What is the percentage increase in sales for the North region from Q1 to Q4 2023?
Practice 8medium
What is the ratio of total annual sales of Software to Services categories?
Practice 9medium
What is the total sales for the West region across all four quarters?
Practice 10medium
By what percentage did Smartphone sales increase from Q3 to Q4 2023?
Practice 11medium
Which region had the highest total sales across all four quarters in 2023?
Practice 12medium
What is the average quarterly sales for the South region in 2023?
Practice 13medium
Which region showed the highest average quarterly sales, and what is that average?
Practice 14medium
What is the profit margin (Profit/Sales × 100) for the Hardware category?
Practice 15medium
By what percentage did North region sales increase from Q1 to Q4?
Practice 16hard
Which region showed the highest average quarterly sales across all four quarters?
Practice 17hard
What is the combined average quarterly revenue for Product C across the first three quarters (Q1, Q2, Q3 of 2023)?
Practice 18hard
By what percentage did the total production increase from Q1 2023 to Q2 2024?
Practice 19hard
If the production growth rate of Product A from Q1 2023 to Q2 2024 continues at the same pace, what would be the expected production of Product A in Q3 2024?
Practice 20hard
What is the percentage increase in North region sales from Q1 to Q4?
60-Second Revision — Mixed DI (2-graph sets)
Remember: Read both graph titles and establish the connection between datasets
Formula: Percentage to absolute = (Percentage × Base value)/100
Trap: Watch for different units between graphs - convert immediately
Strategy: Scan both graphs for 30 seconds before reading any question
Check: Verify which graph contains the data needed for each calculation step
Tip: Use elimination method when calculations become too complex
Time: Maximum 90 seconds per question, move on if stuck beyond this limit