Graduate Management Admission Test (GMAT) Foundational Skills and Error Avoidance Syllabus

What is a key process check to avoid errors when solving equations with fractions?

Clear denominators by multiplying every term by the least common denominator first, reducing the chance of fraction-arithmetic mistakes.

Why should you re-read the final question (the 'question stem prompt') before selecting an answer?

Many traps give the value of an intermediate quantity (e.g. $x$) when the question asks for something else (e.g. $2x$ or $x+1$); re-reading ensures you answer what was actually asked.

In grammar for verbal accuracy, what is subject-verb agreement and a common trap that violates it?

A verb must agree in number with its subject. A common trap inserts a prepositional phrase between them, e.g. 'The box of chocolates *is* (not *are*) on the table'—the subject is 'box', not 'chocolates'.

What is a misplaced (or dangling) modifier, with an example?

A modifier positioned so it appears to describe the wrong noun. E.g. 'Running to the bus, my keys fell out'—the keys are not running; it should be 'Running to the bus, I dropped my keys.'

What is faulty parallelism in a sentence, and how is it corrected?

Items in a list or comparison must share the same grammatical form. 'She likes hiking, swimming, and to bike' is faulty; correct to 'hiking, swimming, and biking.'

What is the rule for pronoun-antecedent agreement?

A pronoun must agree with its antecedent in number and have a single, unambiguous referent. 'Each student must bring *their* book' is non-standard in formal usage; use 'his or her book' or recast in plural.

On the GMAT, when is the use of 'like' correct versus 'as'?

Use 'like' to compare nouns (no verb): 'She runs like a cheetah'; use 'as' to introduce a clause containing a verb: 'She runs as a cheetah does.'

What is the grammatical distinction between 'fewer' and 'less'?

Use 'fewer' for countable nouns ('fewer apples') and 'less' for uncountable/mass nouns ('less water').

What is the difference between 'that' and 'which' in restrictive vs. non-restrictive clauses?

'That' introduces a restrictive (essential) clause with no comma; 'which' introduces a non-restrictive (extra-information) clause set off by commas.

What is the recommended first step when reading dense prose passages on the GMAT?

Identify the passage's main point and structure (purpose of each paragraph) rather than memorizing details, so you can locate specifics later when questions demand them.

What does it mean to map a passage's structure, and why does it aid reading dense prose?

Mapping means noting each paragraph's function (e.g. introduces theory, raises objection, gives evidence). It builds a mental outline that speeds up locating relevant text for detail and inference questions.

What role do transition/signal words play when reading dense prose?

Words like 'however', 'therefore', 'in contrast', and 'for example' flag shifts in argument, contrasts, conclusions, or support, helping you track the logical flow without re-reading.

How should you handle a sentence in dense prose that you do not understand on first read?

Read for the gist and the role the sentence plays in the argument rather than every detail; return to decode it precisely only if a question targets that sentence.

What is the difference between a 'main idea' question and a 'detail' question in Reading Comprehension?

A main-idea question asks for the central thesis or primary purpose of the whole passage; a detail question asks for a specific fact explicitly stated in the text.

What does 'vocabulary in context' require you to determine?

The meaning a word carries in its specific sentence, which may differ from its most common dictionary definition; the surrounding context determines the intended sense.

What is the recommended process for answering a vocabulary-in-context question?

Cover the word, predict a replacement that fits the sentence's logic from context clues, then match your prediction to the closest answer choice.

Why are the most common meanings of a word often trap answers in vocabulary-in-context questions?

Test-writers exploit familiar primary definitions; the tested word frequently uses a secondary or specialized meaning, so the obvious common definition is a deliberate distractor.

What is a common Quant answer trap involving the question 'how many of X are NOT...'?

The trap offers the count that *are* X (the complement). Always note negations like 'not', 'except', or 'least' and answer the exact quantity asked.

What Quant trap arises from assuming a variable is a positive integer?

Unless stated, a variable may be negative, zero, or a fraction. Solutions like $x^{2} = 4$ give $x = 2$ or $x = -2$, and dividing by a variable assumed positive can lose or add solutions.

In a Quant problem, what is the 'partial answer' trap?

An answer choice equals a correct intermediate value rather than the final requested quantity—e.g. you solve for the cost of one item when the question asks for the total cost.

What classic percentage trap involves a price increasing then decreasing by the same percentage?

A rise of $x\%$ followed by a fall of $x\%$ does not return to the original; the net change is a decrease of $\frac{x^{2}}{100}\%$. E.g. $+20\%$ then $-20\%$ gives $0.96$ of the original.

What is the average-speed trap for a round trip at two different speeds?

Average speed is not the arithmetic mean of the speeds. For equal distances use the harmonic mean: $\text{avg speed} = \frac{2 v_1 v_2}{v_1 + v_2}$.

What Data Sufficiency answer trap involves combining statements unnecessarily?

If either statement alone is sufficient, the answer is D, not C. The trap tempts you to combine statements (C) when one alone already suffices.

In Data Sufficiency, what does the 'C trap' specifically refer to?

When the two statements together obviously give the answer, test-takers pick C without checking whether each statement alone is sufficient, missing that the answer may be A, B, or D.

What is a common Verbal (Critical Reasoning) trap answer that is 'out of scope'?

A choice introduces information or a consideration not relevant to the specific argument's conclusion; it may be true or appealing but does not affect the reasoning being evaluated.

In Critical Reasoning strengthen/weaken questions, what is the 'opposite answer' trap?

A tempting choice does the reverse of what is asked—weakening when you need to strengthen, or vice versa—exploiting hasty reading of the question stem.

What is the 'extreme language' trap in Verbal answer choices?

Choices using absolute words like 'always', 'never', 'all', or 'none' are often too strong to be supported by the passage; correct answers tend to use measured language.

In Reading Comprehension, what is the 'true but not the answer' trap?

A choice states something accurate per the passage but does not respond to the specific question asked, so it is wrong despite being factually correct.

What is a Data Insights trap when interpreting a graph or table?

Confusing correlation with causation, or misreading axis scales/units (e.g. logarithmic axes, thousands vs. millions); always confirm what each axis and unit represents before drawing conclusions.

In Data Insights multi-source reasoning, what trap arises from using only one source?

Questions often require synthesizing information across tabs/sources; relying on a single source yields a plausible but incomplete (and wrong) answer. Always check whether other sources are needed.