Simplest form answer

3/21 Simplified = 1/7

3/21 in simplest form is 1/7, found by dividing 3 and 21 by their greatest common factor, 3. As a decimal 1/7 is 0.1429..., and as a percent it is 14.2857...%.

Simplified

1/7

Decimal

0.1429...

Percent

14.2857...%

Step-by-step GCF reduction

1. Find the greatest common factor.

The GCF of 3 and 21 is 3.

2. Divide the numerator and denominator by the GCF.

3 ÷ 3 = 1

21 ÷ 3 = 7

3. Write the result.

3/21 simplified is 1/7.

Decimal and percentage equivalents

Decimal equivalent

1/7 = 0.1429...

Percentage equivalent

1/7 = 14.2857...%

Visual fraction bar

14.2857...%

The filled part represents 1/7 of one whole.

Cite this result

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3/21 in simplest form is 1/7, found by dividing 3 and 21 by their greatest common factor, 3.
ILoveFractions, https://www.ilovefractions.com/tools/fraction-simplifier/3-21/, retrieved September 2, 2026

APA

ILoveFractions. (2026). 3/21 Simplified = 1/7. ILoveFractions.com. Retrieved September 2, 2026, from https://www.ilovefractions.com/tools/fraction-simplifier/3-21/

MLA

"3/21 Simplified = 1/7." ILoveFractions.com, https://www.ilovefractions.com/tools/fraction-simplifier/3-21/. Accessed 2 September 2026.

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