Experience the Quality With Free GRE Exam Questions That Helps Candidates Pass

This is a single-blank Text Completion item testing vocabulary-in-context and critical reading. The sentence presents a claim: short breaks → higher productivity. It then introduces a limitation: the study used self-reported productivity. Self-reports can introduce bias (social desirability, memory errors, or motivated reasoning). The logical consequence is that the conclusion might not be fully warranted yet. “Premature” best captures “drawn too soon given limited evidence,” aligning with GRE Verbal objectives to evaluate claims given methodological constraints. “Unimpeachable” (beyond reproach) contradicts the caveat. “Exhaustive” means comprehensive, which doesn’t match the warning. “Superfluous” means unnecessary or excessive; a conclusion can be unnecessary, but the sentence suggests a timing/justification issue rather than redundancy. Thus “premature” fits both meaning and tone. On the GRE, when a second clause signals limitation (often introduced by “however,” “although,” or “but”), look for an option that reflects caution or undermines certainty appropriately. The test assesses your ability to reconcile claim and qualifier, choosing a word that preserves coherence and accurately reflects the author’s stance toward the evidence quality.

Let xx be liters of the 30% solution and 20−x20-x be liters of the 10% solution. Match total acid:

0.30x+0.10(20−x)=0.18⋅20=3.6.0.30x + 0.10(20 - x) = 0.18 \cdot 20 = 3.6.

Simplify: 0.30x+2−0.10x=3.6⇒0.20x+2=3.6⇒0.20x=1.6⇒x=8.0.30x + 2 - 0.10x = 3.6 \Rightarrow 0.20x + 2 = 3.6 \Rightarrow 0.20x = 1.6 \Rightarrow x = 8.

So, 8 L of 30% and 12 L of 10% yield the 18% target. A quick alligation check gives the same result: place 30 and 10 at the ends with target 18; distances from the target are 12 (30→18) and 8 (18→10). The ratio of amounts is inverse to these distances: 8 (30%) : 12 (10%) → simplifies to 2:3; out of 20 L, that’s 20⋅25=820 \cdot \frac{2}{5} = 8 L of 30%. Common pitfalls include averaging the percentages (which would be valid only for equal volumes) or forgetting the total-volume constraint. Always base on total pure acid, not on the percentages alone.

Clues: “though sometimes abrupt” sets up a concession. The follow-up—“addresses problems directly and expects accountability”—casts the style positively. The blank must signal usefulness or success. “Effective” captures this, making option B correct. “Brusque” echoes “abrupt” but doesn’t reflect the positive outcome. “Inept” and “negligent” contradict effectiveness. On GRE completions, concession markers like “though” guide you: after a drawback, expect a redeeming trait. Here, “effective” resolves that balance.

The sentence contrasts “technical” with a surprising quality that helps lay readers. The blank must signal clarity or ease of understanding. “Accessible” means easy to understand, particularly for non-specialists—perfect fit. “Opaque” and “arcane” both mean obscure or difficult; “recondite” likewise means abstruse. All contradict “enabling lay readers.” On GRE Text Completion, note structural clues: “though often technical” signals contrast; the next clause requires a word meaning “easy to grasp.” Substituting “accessible” yields logical coherence. Wrong answers may tempt by repeating “technical” synonyms, but they must be rejected because the sentence stresses the opposite property.

Cross-multiply: 3x=2(x+2)⇒3x=2x+4⇒x=43x = 2(x+2) \Rightarrow 3x = 2x + 4 \Rightarrow x = 4. Verify in original: 3⋅4/(4+2)=12/6=23\cdot 4 /(4+2) = 12/6 = 2. Domain x≠−2x\ne -2 is satisfied. Option C is correct. Common pitfalls include subtracting incorrectly (e.g., getting x=−4x=-4) or forgetting to check for excluded values that would zero the denominator. On GRE linear rational equations, isolate carefully and always validate the solution.