Percentage to Fraction Table (1/8 to 1/25): 10-Second Calculation Trick for SSC & Bank Exams
Banking Exams5 min readOct 4, 2026

Percentage to Fraction Table (1/8 to 1/25): 10-Second Calculation Trick for SSC & Bank Exams

Percentage to Fraction Table (1/8 to 1/25): 10-Second Calculation Trick for SSC & Bank Exams
5 min read · 939 words

Quick Answer: The 1/8 to 1/25 Percentage-Fraction Table

Percentage to Fraction Table: Master 1/8 to 1/25 in 10 Seconds

Quick Answer: The core values are: 1/8 = 12.5%, 1/9 = 11.11%, 1/11 = 9.09%, 1/12 = 8.33%, 1/6 = 16.67%, 1/7 = 14.28%, 1/16 = 6.25%, and 1/25 = 4%. Memorising the full 1/8 to 1/25 percentage-fraction table lets you replace slow multiplication in discount, interest and data interpretation questions with a single fraction step — cutting average solving time to under 10 seconds in SSC CGL, IBPS PO and UPSC CSAT papers.

Why Percentage-Fraction Equivalence Saves Time in SSC & Bank Exams

In the quantitative aptitude section of SSC CGL and IBPS exams, you typically get less than a minute per question. Multiplying a number like 2,400 by 12.5% the conventional way (convert to 0.125, then multiply) takes three steps and invites decimal errors. Recognising 12.5% as 1/8 lets you simply divide: 2,400 ÷ 8 = 300. One step, no decimals, no slip.

The Staff Selection Commission’s own syllabus documents for combined graduate level examinations explicitly list percentages, profit and loss, and interest as core arithmetic topics — all of which reward fast fraction manipulation (ssc.gov.in). Similarly, IBPS and SBI recruitment tests are speed-driven, which is why toppers consistently memorise the percentage to fraction table before touching mock tests (ibps.in).

Complete Conversion Table: 1/8 to 1/25 With Decimal Values

FractionPercentageDecimal
1/616.67%0.1667
1/714.28%0.1428
1/812.5%0.125
1/911.11%0.1111
1/1010%0.10
1/119.09%0.0909
1/128.33%0.0833
1/137.69%0.0769
1/147.14%0.0714
1/156.67%0.0667
1/166.25%0.0625
1/185.55%0.0555
1/205%0.05
1/244.166%0.0416
1/254%0.04

Also learn these close companions: 1/3 = 33.33%, 1/4 = 25%, 1/5 = 20%, and 1/17 ≈ 5.88%. They combine with the table above constantly in DI sets.

How to Memorise the Table in One Day: Chunking Method

Do not memorise 18 rows as 18 separate facts. Chunk them into four families:

  • Easy tenths and fifths: 1/10 = 10%, 1/20 = 5%, 1/25 = 4%, 1/5 = 20%
  • Half-family: 1/8 = 12.5%, 1/16 = 6.25%, 1/24 = 4.166% (each is half of the previous)
  • Repeating-decimal family: 1/9 = 11.11%, 1/11 = 9.09%, 1/12 = 8.33%, 1/18 = 5.55%
  • 14-family: 1/7 = 14.28%, 1/14 = 7.14%, and the 6-family: 1/6 = 16.67%, 1/15 = 6.67%

Daily plan: 20 minutes in the morning (read + recite), 10 minutes at noon (self-test from fraction side), 10 minutes at night (reverse test — percentage to fraction). One full day of this cycle locks the table in for most aspirants.

Application 1: Discount Problems Solved in 10 Seconds

Example (SSC CGL pattern): A shopkeeper offers a 12.5% discount on an item marked at ₹3,200. Find the selling price.

Standard method: 3,200 × 0.125 = 400; 3,200 − 400 = 2,800. Fraction method: discount = 1/8, so selling price = 7/8 × 3,200 = 7 × 400 = ₹2,800. Two seconds of mental arithmetic.

Example (IBPS PO pattern): After successive discounts of 14.28% and 10%, the final price is ₹1,530. Find the marked price.

14.28% = 1/7 and 10% = 1/10. So price = MP × 6/7 × 9/10 = MP × 54/70. Then 1,530 × 70/54 = ₹1,983.33… check: since numbers should be clean, exams usually pick 14.28% with numbers divisible by 7 — always verify divisibility before committing.

Application 2: Simple and Compound Interest Numericals

Simple interest: SI at 8.33% p.a. on ₹6,000 for 3 years. Since 8.33% = 1/12, yearly interest = 6,000 ÷ 12 = 500. SI = 500 × 3 = ₹1,500.

Compound interest (2 years): CI at 12.5% p.a. on ₹4,096. Here 12.5% = 1/8, so amount = 4,096 × 9/8 × 9/8 = 5,184. CI = 5,184 − 4,096 = ₹1,088. Notice how the fraction route avoids multiplying by 1.125 twice.

For 6.67% (= 1/15) and 16.67% (= 1/6), the same shortcut applies — each year multiply by (denominator + 1)/denominator.

Application 3: Data Interpretation and Successive Percentage Change

Successive change of a% then b% equals a + b + ab/100. With fractions, this becomes trivial: an 8.33% increase (= 1/12) followed by a 12.5% decrease (= 1/8) gives net change = 12 − 8.33 − (100/12) ≈ use fractions directly: × 13/12 × 7/8 = 91/96, a net decrease of about 5.2%.

In DI tables and pie charts, values like 25%, 12.5%, 16.67% and 33.33% appear constantly because they represent 1/4, 1/8, 1/6 and 1/3 of a total. Recognising 108° in a pie chart as 30% (108/360 = 3/10) comes from the same muscle.

Common Mistakes Aspirants Make With Fraction-Percentage Conversion

  • Confusing 1/8 with 1/12: 1/8 = 12.5% but 1/12 = 8.33%. Swapping them changes discount answers completely.
  • Forgetting the repeating part: 1/6 = 16.67%, not 16.67 exactly — in multi-step DI, small rounding errors compound.
  • Wrong successive-change sign: an increase of 1/12 means × 13/12, not × 11/12.
  • Mixing up 14.28% and 14.2857%: 1/7 = 14 2/7 % — remember “14 and two-sevenths”.
  • Applying the fraction to the wrong base: in successive discounts, each fraction applies to the reduced price, not the marked price.

Practice Questions With Step-by-Step Solutions

  1. Q: 16.67% of 726 = ? — S: 1/6 × 726 = 726 ÷ 6 = 121.
  2. Q: A trader marks a shirt at ₹960 and gives a 6.25% discount. Selling price? — S: 6.25% = 1/16; SP = 15/16 × 960 = ₹900.
  3. Q: SI on a sum at 6.25% p.a. for 4 years is ₹500. Find the sum. — S: yearly SI = 125 = P/16, so P = ₹2,000.
  4. Q: CI on ₹2,048 at 12.5% for 2 years? — S: 2,048 × 9/8 × 9/8 = 2,592; CI = ₹544.
  5. Q: A number is increased by 11.11% then decreased by 10%. Net change? — S: × 10/9 × 9/10 = 1 → 0% net change.
  6. Q: A price rises by 8.33%. By what fraction must it fall to return to the original? — S: rise = 1/12 (now 13/12); fall needed = 1/13 = 7.69%.
  7. Q: 37.5% of 640 = ? — S: 37.5% = 3/8; 3/8 × 640 = 240.
  8. Q: Two successive discounts of 14.28% each. Net discount? — S: × 6/7 × 6/7 = 36/49; net discount = 13/49 ≈ 26.53%.
  9. Q: In a pie chart, a sector is 45°. What fraction of the whole? — S: 45/360 = 1/8 = 12.5%.
  10. Q: If 1/12 of a number is 96, what is 25% of that number? — S: number = 1,152; 25% = 1/4 → 288.

Reverse Table: Percentage to Fraction Quick Reference

PercentageFraction
4%1/25
5%1/20
5.55%1/18
6.25%1/16
6.67%1/15
7.14%1/14
7.69%1/13
8.33%1/12
9.09%1/11
10%1/10
11.11%1/9
12.5%1/8
14.28%1/7
16.67%1/6

Memory Tips and Revision Strategy for Exam Day

Use spaced revision: Day 1 (learn chunks), Day 2 (self-test), Day 4, Day 7, then weekly until the exam. Make physical flashcards — fraction on the front, percentage on the back — and shuffle so you practise both directions. Under exam pressure, anchor to the “half-chain”: 25% → 12.5% → 6.25% → 4.166% (1/4, 1/8, 1/16, 1/24). If you blank out, quickly derive: multiply the fraction by 100 (e.g., 1/8 × 100 = 100/8 = 12.5). Practise 10 DI questions daily using only the table; within a week, recall becomes automatic.

Frequently Asked Questions

Q: What is 1/8 as a percentage?

1/8 = 12.5%. Divide 100 by 8 to get 12.5. In discount problems, a 12.5% discount means the selling price is 7/8 of the marked price — one division instead of a decimal multiplication.

Q: How do I convert any fraction to a percentage quickly?

Multiply the fraction by 100. For denominators 8–25, memorise the shortcut patterns above: halves chain (8→16→24), nines/elevens (repeating digits 11.11 and 9.09), and sevenths (“14 and two-sevenths”).

Q: Which fraction-percentage values are most important for SSC CGL?

1/8 (12.5%), 1/12 (8.33%), 1/16 (6.25%) and 1/6 (16.67%) appear most frequently in DI and arithmetic — prioritise these four, then 1/7 and 1/9.

Q: Can this table be used for compound interest questions?

Yes. For 12.5% (= 1/8) over two years, compute the amount as P × 9/8 × 9/8 — successive fraction multiplication replaces repeated decimal multiplication and is far less error-prone.

Q: How long does it take to memorise the 1/8 to 1/25 table?

With chunked practice and three short revision slots a day, most aspirants memorise the full table in 1–2 days; spaced revision over a week makes it permanent.

Related reading

Quick revision

  • Easy tenths and fifths: 1/10 = 10%, 1/20 = 5%, 1/25 = 4%, 1/5 = 20%
  • Half-family: 1/8 = 12.5%, 1/16 = 6.25%, 1/24 = 4.166% (each is half of the previous)
  • Repeating-decimal family: 1/9 = 11.11%, 1/11 = 9.09%, 1/12 = 8.33%, 1/18 = 5.55%
  • 14-family: 1/7 = 14.28%, 1/14 = 7.14%, and the 6-family: 1/6 = 16.67%, 1/15 = 6.67%
  • Confusing 1/8 with 1/12: 1/8 = 12.5% but 1/12 = 8.33%. Swapping them changes discount answers completely.
  • Forgetting the repeating part: 1/6 = 16.67%, not 16.67 exactly — in multi-step DI, small rounding errors compound.
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