Simplest form answer

21/105 Simplified = 1/5

21/105 in simplest form is 1/5, found by dividing 21 and 105 by their greatest common factor, 21. As a decimal 1/5 is 0.2, and as a percent it is 20%.

Simplified

1/5

Decimal

0.2

Percent

20%

Step-by-step GCF reduction

1. Find the greatest common factor.

The GCF of 21 and 105 is 21.

2. Divide the numerator and denominator by the GCF.

21 ÷ 21 = 1

105 ÷ 21 = 5

3. Write the result.

21/105 simplified is 1/5.

Decimal and percentage equivalents

Decimal equivalent

1/5 = 0.2

Percentage equivalent

1/5 = 20%

Visual fraction bar

20%

The filled part represents 1/5 of one whole.

Cite this result

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21/105 in simplest form is 1/5, found by dividing 21 and 105 by their greatest common factor, 21.
ILoveFractions, https://www.ilovefractions.com/tools/fraction-simplifier/21-105/, retrieved September 2, 2026

APA

ILoveFractions. (2026). 21/105 Simplified = 1/5. ILoveFractions.com. Retrieved September 2, 2026, from https://www.ilovefractions.com/tools/fraction-simplifier/21-105/

MLA

"21/105 Simplified = 1/5." ILoveFractions.com, https://www.ilovefractions.com/tools/fraction-simplifier/21-105/. Accessed 2 September 2026.

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