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Percent to Fraction & Fraction to Percent — Instant Conversion

Learn to convert any percentage to a fraction and vice versa instantly, with the core concept and basic conversion table for 1/1 through 1/100

Percent to Fraction & Fraction to Percent

What is Percent?

Percent = Per + Cent = Per 100

The symbol % simply means × 1/100.

Example: Find the percent of 360/600.

  • 600 → 360
  • 1 → 360/600
  • 100 → (360/600) × 100 = 60%

Percentage → Fraction

Multiply the percentage by 1/100

Percentage Calculation Fraction
10% 10 × 1/100 1/10
5% 5 × 1/100 1/20
20% 20 × 1/100 1/5
25% 25 × 1/100 1/4
16⅔% (= 50/3%) 50/3 × 1/100 1/6
40% 40 × 1/100 2/5

Fraction → Percentage

Multiply the fraction by 100

Fraction Calculation Percentage
1/10 1/10 × 100 10%
1/20 1/20 × 100 5%
1/5 1/5 × 100 20%
1/6 1/6 × 100 16⅔% or 16.67%

The Master Conversion Table (1/n)

Memorize these — they appear in almost every quant problem:

Fraction Percentage Fraction Percentage Fraction Percentage
1/1 100% 1/10 10% 1/19 5.26%
1/2 50% 1/11 9.09% 1/20 5%
1/3 33.33% 1/12 8.33% 1/24 4.17%
1/4 25% 1/13 7.69% 1/25 4%
1/5 20% 1/14 7.14% 1/30 3.33%
1/6 16.67% 1/15 6.66% 1/40 2.5%
1/7 14.28% 1/16 6.25% 1/50 2%
1/8 12.5% 1/17 5.88% 1/100 1%
1/9 11.11% 1/18 5.55%

Exam tip: Recognizing 11.11% as 1/9, or 14.28% as 1/7 instantly saves 30+ seconds per question. These appear constantly in ratio, percentage, profit/loss, and SI/CI problems.


The Multiplier Trick

Once you know 1/n as a percentage, any multiple k/n = k × (1/n)%.

Examples with 1/2 = 50%:

Fraction = Multiplier × 50% Percentage
3/2 3 × 50% 150%
4/2 4 × 50% 200%
5/2 5 × 50% 250%
9/2 9 × 50% 450%

This works for ANY denominator — just multiply the numerator by the base percentage.


Practice: Quick-Fire Conversions

# Convert Answer
1 12.5% → fraction 1/8
2 1/7 → percentage 14.28%
3 33.33% → fraction 1/3
4 1/16 → percentage 6.25%
5 7.14% → fraction 1/14
6 1/25 → percentage 4%
7 9.09% → fraction 1/11
8 1/40 → percentage 2.5%

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