Data Adequacy & Data Interpretation
What Data Adequacy & Data Interpretation tests
This section combines DI sets (tables, bar and line graphs, pie charts, caselets) with data sufficiency. DI asks you to compute or compare values from supplied data; DA asks whether the statements give enough information to answer a question, without requiring the full numerical answer.
Core rules
- DI: Read the title, units, axes, and footnotes before calculating. Use approximations and percentage shortcuts; compute only the quantity asked.
- Distinguish percentage from percentage points, and 'percent of total' from 'percent more than'.
- DA: Treat the question stem and each statement separately. Test statement (1) alone, then (2) alone, then both together. Do not carry information from one statement into the other unless evaluating them together.
- In DA, stop as soon as sufficiency is decided; a unique value is needed, not the value itself.
Worked example
Question: What is the value of x? (1) x squared = 16 (2) x > 0. Statement (1) gives x = 4 or -4: not sufficient. Statement (2) alone does not fix x: not sufficient. Together, x must be positive, so x = 4: sufficient. Answer: both statements together are sufficient, but neither alone is.
Traps
Using a pie-chart label as an absolute value when it is a percentage; averaging percentages without weighting; in DA, assuming a statement is sufficient because it produces an equation; forgetting that a statement may give two valid values.