Friday Puzzle Quiz: 15 Quant Shortcuts and Reasoning MCQs Solved Fast

Quick Answer: You can solve 15 quant and reasoning MCQs in under 12 minutes by setting a 30–50 second timer target per question and using shortcut-first methods: fraction-percentage conversion for percentages, the difference-ratio-alternate check order for number series, and Venn diagram elimination for syllogisms. This quiz gives you five questions per topic, per-question time targets, and a full answer key showing exactly where aspirants lose seconds.

Quiz Rules and Per-Question Timer Targets

Before you start, keep a stopwatch running. The total budget is 12 minutes (720 seconds) for 15 questions, which works out to an average of 48 seconds per question. However, not every question deserves equal time:

• Percentage MCQs (Q1–Q5): 30–40 seconds each — these should be the fastest once conversions are memorised.
• Number Series MCQs (Q6–Q10): 40–50 seconds each — pattern detection takes a few extra seconds.
• Syllogism MCQs (Q11–Q15): 35–45 seconds each — Venn diagrams become mechanical with practice.

Rule: if you cross 60 seconds on any single question, mark it for review, pick the most likely option, and move on. Sectional mocks published by the Staff Selection Commission and banking exam bodies repeatedly show that time management, not knowledge, separates selected candidates from near-misses.

Section A: Percentage Shortcuts MCQs (Q1–Q5)

Use the fraction-percentage conversion table (given below as Shortcut 1) for every question in this section.

Q1. What is 37.5% of 640?
(a) 220 (b) 240 (c) 250 (d) 260

Q2. If the price of an item rises by 25% and then falls by 20%, what is the net percentage change?
(a) 5% increase (b) 5% decrease (c) No change (d) 2% decrease

Q3. A number is increased by 16.66%. Which fraction of the original number does the increase equal?
(a) 1/5 (b) 1/6 (c) 1/7 (d) 1/4

Q4. In an exam, a student scores 87.5% and misses the maximum by 75 marks. What is the total marks?
(a) 560 (b) 600 (c) 640 (d) 680

Q5. If A’s salary is 33.33% more than B’s, then B’s salary is what per cent of A’s?
(a) 75% (b) 80% (c) 66.66% (d) 70%

Section B: Number Series Shortcuts MCQs (Q6–Q10)

Apply Shortcut 3: check differences first, then ratios, then alternate patterns — in that fixed order, never randomly.

Q6. 7, 10, 16, 28, 52, ?
(a) 96 (b) 100 (c) 104 (d) 92

Q7. 4, 12, 36, 108, ?
(a) 216 (b) 324 (c) 296 (d) 360

Q8. 2, 3, 5, 8, 13, 21, ?
(a) 30 (b) 32 (c) 34 (d) 36

Q9. 5, 11, 23, 47, ?
(a) 95 (b) 94 (c) 96 (d) 93

Q10. 240, 120, 40, 10, ?
(a) 2 (b) 5 (c) 4 (d) 3

Section C: Syllogism Reasoning MCQs (Q11–Q15)

Use the Venn diagram elimination method (Shortcut 4). Draw the minimal diagram for the statements, then eliminate every conclusion that your diagram violates.

Q11. Statements: All pens are books. Some books are copies.
Conclusions: I. Some pens are copies. II. Some copies are books.
(a) Only I follows (b) Only II follows (c) Both follow (d) Neither follows

Q12. Statements: All cats are animals. No animal is a plant.
Conclusions: I. No cat is a plant. II. Some plants are animals.
(a) Only I follows (b) Only II follows (c) Both follow (d) Neither follows

Q13. Statements: Some mangoes are sweet. All sweets are desserts.
Conclusions: I. Some mangoes are desserts. II. All desserts are sweet.
(a) Only I follows (b) Only II follows (c) Both follow (d) Neither follows

Q14. Statements: All teachers are graduates. Some graduates are readers.
Conclusions: I. Some teachers are readers. II. Some readers are graduates.
(a) Only I follows (b) Only II follows (c) Both follow (d) Neither follows

Q15. Statements: No chair is a table. Some tables are wooden.
Conclusions: I. Some wooden things are tables. II. No wooden thing is a chair.
(a) Only I follows (b) Only II follows (c) Both follow (d) Neither follows

Shortcut 1: Fraction-Percentage Conversion Table

Memorise this table until recall is instant. Every percentage question in Section A becomes mental arithmetic once these are internalised:

So 37.5% = 3/8, and Q1 becomes 3/8 × 640 = 240 in about five seconds.

Shortcut 2: Successive Percentage Formula

For chained percentage changes, apply a + b + ab/100, where a and b are the two successive changes (use negative signs for decreases). For Q2: 25 − 20 + (25 × −20)/100 = 5 − 5 = 0%, i.e., no net change. This formula is mathematically exact, derived directly from the multiplier (1 + a/100)(1 + b/100), not an approximation — which is why it is safe for SSC and banking exams.

Shortcut 3: Series Pattern Detection in 10 Seconds

Follow this fixed check order every time:

1. Differences: Subtract consecutive terms. If differences are equal or form their own series (Q6: differences 3, 6, 12, 24 double each time → next difference 48 → 100), you are done.
2. Ratios: Divide consecutive terms. Q7 is a pure ×3 series; Q10 divides by 2, 3, 4, then 5.
3. Alternate patterns: Check odd-position and even-position terms separately, or Fibonacci-style addition (Q8: each term is the sum of the previous two → 13 + 21 = 34).
4. Mixed operations: Q9 follows ×2 + 1, so the answer is 47 × 2 + 1 = 95.

Shortcut 4: Syllogism Elimination Method

Draw the minimal Venn diagram for the statements — circles that just satisfy the given conditions, nothing more. Then test each conclusion: if any valid position of the circles makes the conclusion false, it does not follow. In Q11, the pens circle sits inside books, and the copies circle only partly overlaps books — there is no forced overlap with pens, so Conclusion I fails while II is simply the converse of a given statement and follows. With practice, each diagram should take under 15 seconds. For structured practice in reasoning, resources from IndiaBIX and official syllabus PDFs on ssc.gov.in are reliable references.

Answer Key with Time Analysis

Where aspirants lose time: Q4 (setting up the equation instead of using 1/8), Q6 (checking ratios before differences), and Q15 (drawing elaborate diagrams instead of minimal ones). In Q13, Conclusion II (“All desserts are sweet”) reverses “All sweets are desserts” — a classic trap; reversal of a universal affirmative is never valid. In Q15, II fails because wooden things may extend beyond tables and overlap chairs.

Score Interpretation and Next Practice Steps

• 13–15 correct under 12 minutes: Exam-ready for SSC CGL Tier-I and banking prelims quant-reasoning sections. Move to full-length 60-minute mocks.
• 10–12 correct: Strong core; revise the conversion table and drill 20 syllogisms daily for a week.
• 7–9 correct: Concepts are fine, speed is the issue. Redo this quiz after three days aiming to cut 90 seconds from your total.
• Below 7: Relearn percentage basics and Venn diagram rules before attempting timed sets again — timing an unsteady foundation builds bad habits.

Next drill: alternate this set with a 25-question data interpretation set and a 15-question coding-decoding set across the week, always writing your per-question time beside each attempt.

Frequently Asked Questions

Q: How much time should I spend on each quant MCQ in competitive exams?

Roughly 30–50 seconds per question; aim for under 48 seconds on average to finish 15 MCQs in 12 minutes. Anything beyond 60 seconds should be parked for review.

Q: Are shortcut methods reliable for SSC and banking exams?

Yes. Standard shortcuts like fraction-percentage conversion and the successive percentage formula (a + b + ab/100) are mathematically exact, derived from first principles — not approximations — so they are fully safe for official exams.

Q: How do I improve speed in syllogism questions?

Practise the Venn diagram elimination method until drawing a minimal diagram takes under 15 seconds. Speed comes from diagram economy, not from reading conclusions faster.

Q: What is the ideal order to attempt mixed quant and reasoning sections?

Attempt your strongest topic first to bank marks quickly, then number series (high accuracy, moderate speed), then syllogisms, leaving multi-step word problems for last.

Q: How many timed quizzes should I take weekly for exam prep?

Two to three timed mixed sets per week with a time analysis after each attempt is sufficient for measurable improvement. Analysis matters more than volume.

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