PERA CET common mistakes
PERA CET · Understand the traps and how to avoid them.
Spending more than about 90 seconds on a single aptitude question before deciding to skip it, then losing the time needed for later easy questions.
Under exam pressure, candidates treat every question as equally important and fear leaving a blank, so they keep reworking the same calculation instead of triaging.
What to do instead
Adopt a two-pass strategy: in pass one, answer only questions you can finish in under 90 seconds and mark the rest; in pass two, return to marked questions with the remaining time. Practise with a visible timer so the 90-second cut-off becomes automatic.
Losing marks on percentage, ratio and average problems because the base value is misidentified (for example, taking the original price instead of the new price as the base for a successive discount).
Candidates memorise formulas such as successive percentage change but do not track which quantity is the reference value, and word problems deliberately obscure the base.
What to do instead
Before calculating, write one line stating 'base = ___' and express every percentage as a fraction of that base. For successive changes, use the multiplier method (1 ± a)(1 ± b) rather than adding percentages, and verify with a quick numerical sanity check.
Making arithmetic slips in time-and-work, speed-distance and pipe-cistern problems by mixing units (minutes with hours, metres with kilometres) within the same equation.
These problems embed unit changes in the wording, and candidates convert mentally while also handling the main logic, so the conversion is dropped under time pressure.
What to do instead
Convert all quantities to one unit set before writing any equation, and annotate the unit next to each number. Use the LCM or efficiency method for work problems so fractions are avoided, and re-read the question once to confirm the unit the answer must be in.
Guessing on data interpretation sets without reading the axis labels, units or footnotes, leading to answers that are numerically plausible but wrong by a factor of 10 or 100.
Candidates jump to the first number they see in a table or chart and compute immediately, skipping the legend and scale that the setter used to create distractors.
What to do instead
Spend the first 15 seconds of every DI set reading the title, axis units, legend and any note. Then estimate the answer roughly before computing; if the computed value differs from the estimate by an order of magnitude, recheck the units.
Treating 'not', 'except', 'least', 'cannot' and 'only' as neutral words and choosing the option that is true rather than the one the question asks for.
The brain processes the positive content of an option faster than the negation in the stem, so a true statement feels like a correct answer even when the stem asks for the false one.
What to do instead
Underline or circle the qualifier in the stem before reading the options, and restate the task in your own words ('I need the option that is NOT true'). After choosing, re-read the stem once to confirm the option matches the qualifier.
Solving syllogisms and seating/ranking puzzles from intuition or a mental picture instead of drawing a diagram, then missing the second valid conclusion or one possible arrangement.
These items are designed with multiple valid conclusions or arrangements, and working memory cannot hold all constraints simultaneously under time pressure.
What to do instead
Use a fixed notation: Venn diagrams for syllogisms, a line with numbered seats for linear arrangements, a circle sketch for circular ones. For 'either/or' conclusion pairs, test whether the two conclusions are complementary before marking them.
Assuming a stated relationship in blood-relation or direction-sense puzzles is between the speaker and the subject, rather than drawing the full family tree or path.
The wording ('pointing to a man, she said...') invites a shortcut identification, and candidates answer about the wrong pair of people.
What to do instead
Always draw the tree or path with a symbol key (male/female, vertical for generations, horizontal for siblings/spouses) and label each node. Answer only after locating the exact two nodes the question names.
Choosing an English option because it 'sounds right' in a sentence-completion or error-spotting item, without checking subject-verb agreement, tense consistency and preposition collocation.
Candidates rely on spoken-language intuition, which tolerates errors that written grammar tests penalise, and distractor options are written to sound natural.
What to do instead
Run a three-point check on every candidate answer: does the verb agree with its subject, does the tense match the rest of the sentence, and is the preposition the standard collocation? Eliminate options that fail any check before selecting.
Answering reading-comprehension questions from prior knowledge or from a single matching keyword, instead of locating the line in the passage that supports the option.
Keyword matching feels efficient under time pressure, and distractors are deliberately built with words copied from the passage but with a changed scope or inference.
What to do instead
For each question, find and underline the supporting sentence before looking at the options, then reject any option that goes beyond or contradicts it. For inference questions, prefer the option that requires the smallest logical step from the stated text.
Rushing current-affairs and static-GK items by pattern-matching a familiar name, without checking the specific qualifier (year, first/largest, state, appointment order).
GK questions often pair a well-known entity with a subtle qualifier, and candidates recognise the name and stop reading the rest of the stem.
What to do instead
Read the full stem and note the qualifier before answering, and keep a short revision sheet of 'firsts', 'largest/smallest', capitals, currencies and recent appointments. If two options both seem true, choose the one that matches every qualifier in the stem, and skip rather than guess when no qualifier match exists.