Tables

Tabular data interpretation questions

30 practice questionsPage updated 25 Sept 2026Reviewed by AISEA Editorial DeskPractice questions

Tables organise numerical information so that you can compare values, calculate totals and identify relationships quickly. Table-based data interpretation questions reward disciplined reading: confirm the row, column, unit and time period before calculating. Keep the original quantities visible, choose the denominator deliberately and check whether the question asks for a total, ratio, average, rate or percentage.

Key formulas and rules

5 rules

Percentage of total: $\text{Percentage} = \frac{\text{Part}}{\text{Whole}} \times 100$

Percentage change: $\%\Delta = \frac{\text{New Value} - \text{Old Value}}{\text{Old Value}} \times 100$

Weighted average: $\bar{x} = \frac{\sum (x_i \times w_i)}{\sum w_i}$

Ratio of A to B: $A : B = \frac{A}{B}$ (ensure identical units before comparing)

Profit margin: $\text{Profit Margin} = \frac{\text{Revenue} - \text{Cost}}{\text{Revenue}} \times 100\%$

Key concepts

Read the table before calculating

Identify the title, units, row labels, column labels and time period. A value of 120 may mean 120 rupees, lakhs, tonnes or people. A percentage may be a rate already calculated, not a quantity to add. Restate the relevant row or cells in words before applying a formula.

Totals and subtotals

Add values only when they measure the same thing and use the same unit. For a row total, add across columns; for a column total, add down rows. If a table gives subtotals and a grand total, use the smallest set of figures that answers the question to avoid double-counting.

Worked examples

Example 1

| Year | 2019 | 2020 | 2021 | 2022 | 2023 |

Year	2019	2020	2021	2022	2023
Sales (₹ lakhs)	120	150	180	200	240

What was the percentage increase in sales from 2019 to 2023?

Solution

Step 1: Old sales = 120 lakhs and new sales = 240 lakhs.
Step 2: Increase = 240 − 120 = 120 lakhs.
Step 3: Percentage increase = (120 / 120) × 100 = 100%.
Answer: 100%.

Example 2

Student	Mathematics	Science	English
A	85	78	92
B	72	88	85
C	90	82	78

What is the arithmetic mean of the Science marks?

Solution

Step 1: Science marks are 78, 88 and 82.
Step 2: Sum = 78 + 88 + 82 = 248.
Step 3: Number of students = 3.
Step 4: Mean = 248 / 3 = 82.666..., which is 82.67 to two decimal places.
Answer: 82.67 marks.

Example 3

| Year | 2020 | 2021 | 2022 | 2023 |

Year	2020	2021	2022	2023
Production (tonnes)	500	600	720	800
Sales (tonnes)	450	550	650	750

In which year was sales as a percentage of production the highest?

Solution

Step 1: Calculate sales / production for each year.
2020: 450 / 500 = 90%.
2021: 550 / 600 = 91.67%.
2022: 650 / 720 ≈ 90.28%.
2023: 750 / 800 = 93.75%.
Step 2: Compare the four percentages, not the raw sales values.
Answer: 2023, at 93.75%.

Example 4

| Department | Employees | Average salary (₹) |

Department	Employees	Average salary (₹)
IT	50	50,000
HR	30	40,000
Sales	40	45,000
Finance	20	60,000

Find the weighted average salary.

Solution

Step 1: Total employees = 50 + 30 + 40 + 20 = 140.
Step 2: Total salary represented = (50 × 50,000) + (30 × 40,000) + (40 × 45,000) + (20 × 60,000) = 6,700,000.
Step 3: Weighted average = 6,700,000 / 140 = ₹47,857.14 approximately.
Answer: ₹47,857.14, or about ₹47,857 per employee.

Example 5

| Region | Revenue (₹ crore) | Cost (₹ crore) |

Region	Revenue (₹ crore)	Cost (₹ crore)
North	200	150
South	180	120
East	120	100
West	150	110

Which region has the highest profit margin?

Solution

Step 1: Profit = revenue − cost.
North: 50 / 200 = 25%.
South: 60 / 180 = 33.33%.
East: 20 / 120 = 16.67%.
West: 40 / 150 = 26.67%.
Step 2: Profit margin divides profit by that region's own revenue.
Answer: South, with a margin of approximately 33.33%.

Example 6

| Month | Income (₹) | Expenditure (₹) |

Month	Income (₹)	Expenditure (₹)
January	30,000	25,000
February	35,000	28,000
March	40,000	32,000
April	38,000	30,000

What are the total savings over the four months?

Solution

Step 1: January savings = 30,000 − 25,000 = 5,000.
Step 2: February savings = 35,000 − 28,000 = 7,000.
Step 3: March savings = 40,000 − 32,000 = 8,000.
Step 4: April savings = 38,000 − 30,000 = 8,000.
Step 5: Total savings = 5,000 + 7,000 + 8,000 + 8,000 = ₹28,000.
Answer: ₹28,000.

Example 7

A table reports that a pass rate increased from 20% in one year to 30% in the next. What is the difference in percentage points, and what is the relative percentage increase?

Solution

Step 1: Difference in percentage points = 30% − 20% = 10 percentage points.
Step 2: Relative percentage increase uses the old rate as the denominator: (10 / 20) × 100 = 50%.
Answer: The pass rate increased by 10 percentage points, which is a 50% relative increase.

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Tables

Key formulas and rules

Key concepts

Read the table before calculating

Totals and subtotals

Percentages and percentage points

Ratios, rates and comparisons

Mean and weighted average

Trends and extreme values

Cross-check the calculation

Common table traps

Worked examples

Example 1

Example 2

Example 3

Example 4

Example 5

Example 6

Example 7

Representative solved questions

Question 1

Question 2

Question 3

Common mistakes and useful habits

Sources and review notes

Ready to test your understanding?

Key formulas and rules

Key concepts

Read the table before calculating

Totals and subtotals

Percentages and percentage points

Ratios, rates and comparisons

Mean and weighted average

Trends and extreme values

Cross-check the calculation

Common table traps

Worked examples

Example 1

Example 2

Example 3

Example 4

Example 5

Example 6

Example 7

Representative solved questions

Question 1

Question 2

Question 3

Common mistakes and useful habits

Sources and review notes

Ready to test your understanding?

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