Guide4 patterns

Data Sufficiency / Statement Evaluation

True / False / Cannot-say judgements from given data.

Statement evaluation

The method

Compute the quantity the statement claims from the exhibit, then judge True or False. 'Cannot say' applies only when the data needed is genuinely not shown.

Worked example

Based on the table, decide: ‘North region sales were more than double South region sales.’

Answer: True

Double South = 2 × 450 = 900. North = 920, which is more than 900, so the statement is True. (Both figures are shown, so 'Cannot say' does not apply.)

Cannot say

The method

Check whether the exhibit actually contains the data the statement needs. If it isn't derivable from what's shown, the answer is Cannot say — not False.

Data sufficiency

The method

Test each statement alone for whether it pins down the answer, then both together; choose the matching sufficiency option.

Worked example

Is the number x greater than 50? (1) x is greater than 40. (2) x is a multiple of 30.

Answer: Both together are sufficient, but neither alone

Statement (1): x could be 45 (≤50) or 60 (>50) — insufficient. Statement (2): x could be 30 or 60 — insufficient. Together: x>40 and a multiple of 30 means x is 60, 90, … always > 50 — sufficient. So BOTH together, neither alone.

Quantity comparison

The method

Evaluate both quantities exactly, then compare; pick 'cannot determine' only if the relationship genuinely varies.

Worked example

Column A: 25% of 80. Column B: 80% of 25. Which is greater?

Answer: The two quantities are equal

Column A = 0.25 × 80 = 20. Column B = 0.80 × 25 = 20. They are equal — 'a% of b' always equals 'b% of a'. The trap is assuming the larger percentage wins.