Simplest form answer

18/21 Simplified = 6/7

18/21 in simplest form is 6/7, found by dividing 18 and 21 by their greatest common factor, 3. As a decimal 6/7 is 0.8571..., and as a percent it is 85.7143...%.

Simplified

6/7

Decimal

0.8571...

Percent

85.7143...%

Step-by-step GCF reduction

1. Find the greatest common factor.

The GCF of 18 and 21 is 3.

2. Divide the numerator and denominator by the GCF.

18 ÷ 3 = 6

21 ÷ 3 = 7

3. Write the result.

18/21 simplified is 6/7.

Decimal and percentage equivalents

Decimal equivalent

6/7 = 0.8571...

Percentage equivalent

6/7 = 85.7143...%

Visual fraction bar

85.7143...%

The filled part represents 6/7 of one whole.

Cite this result

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18/21 in simplest form is 6/7, found by dividing 18 and 21 by their greatest common factor, 3.
ILoveFractions, https://www.ilovefractions.com/tools/fraction-simplifier/18-21/, retrieved September 2, 2026

APA

ILoveFractions. (2026). 18/21 Simplified = 6/7. ILoveFractions.com. Retrieved September 2, 2026, from https://www.ilovefractions.com/tools/fraction-simplifier/18-21/

MLA

"18/21 Simplified = 6/7." ILoveFractions.com, https://www.ilovefractions.com/tools/fraction-simplifier/18-21/. Accessed 2 September 2026.

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