Data Interpretation made clear.
Read the heading, units and denominator before calculating. Data interpretation is not a separate formula list: it combines accurate reading with ratios, averages and percentages.
Key concepts in Data Interpretation
Totals and units
Check whether values represent people, thousands of rupees, percentages or cumulative totals.
Percentage share
Part/whole × 100. Identify which row, column or grand total is the whole.
Growth
(new−old)/old × 100; the earlier value is the base.
Comparisons
A large absolute increase does not necessarily mean a large percentage increase.
Sales dataset used in the examples
| Month | Units | Quarter share |
|---|---|---|
| January | 40 | 26⅔% |
| February | 60 | 40% |
| March | 50 | 33⅓% |
| Total | 150 | 100% |
A reliable solving method
- Read labels and time periods before looking at the options.
- Copy only the values needed for the question.
- Write the numerator and denominator with labels.
- Estimate the result, then calculate and check the units.
Step-by-step solved examples
A shop sells 40, 60 and 50 units in January, February and March. Find total and average.
- Total = 40+60+50 = 150 units.
- There are three months.
- Average = 150/3 = 50 units per month.
Using those figures, find February’s share of the quarter.
- February contributes 60 of the 150 units.
- Share = 60/150 × 100.
- February accounts for 40%.
Find percentage growth from January’s 40 to February’s 60.
- Increase = 60−40 = 20 units.
- The base is January’s 40, not February’s 60.
- Growth = 20/40 × 100 = 50%.
Data Interpretation: practice questions
Choose one answer before opening the explanation. Write down your reasoning as well as the option; a correct guess is different from a method you can repeat.
Sales are 20,30,50 units across three regions. Total?
Show answer and explanation — question 1
Answer C: 100
20+30+50 = 100.
In that data, second region’s share?
Show answer and explanation — question 2
Answer C: 30%
30/100 × 100 = 30%.
Sales grow from 80 to 100. Growth?
Show answer and explanation — question 3
Answer B: 25%
20/80 × 100 = 25%.
Average of 30,45,60?
Show answer and explanation — question 4
Answer B: 45
135/3 = 45.
A chart is in thousands. A value of 12 means?
Show answer and explanation — question 5
Answer D: 12,000
12 × 1000 = 12,000.
A rises 10→20; B rises 100→120. Which has greater percentage growth?
Show answer and explanation — question 6
Answer A: A
A grows 100%; B grows 20%, although B adds more units.
Frequently asked questions
Should I calculate every entry?
No. Work only with the rows or periods needed for the question.
How should I round?
Keep the fraction or extra decimal places during intermediate steps; round only as requested at the end.
Read labels and time periods before looking at the options. Estimate the result, then calculate and check the units.