Simplest form answer

42/105 Simplified = 2/5

42/105 in simplest form is 2/5, found by dividing 42 and 105 by their greatest common factor, 21. As a decimal 2/5 is 0.4, and as a percent it is 40%.

Simplified

2/5

Decimal

0.4

Percent

40%

Step-by-step GCF reduction

1. Find the greatest common factor.

The GCF of 42 and 105 is 21.

2. Divide the numerator and denominator by the GCF.

42 ÷ 21 = 2

105 ÷ 21 = 5

3. Write the result.

42/105 simplified is 2/5.

Decimal and percentage equivalents

Decimal equivalent

2/5 = 0.4

Percentage equivalent

2/5 = 40%

Visual fraction bar

40%

The filled part represents 2/5 of one whole.

Cite this result

Quoting this answer in homework, a lesson plan, or an article? Copy a ready-made citation.

42/105 in simplest form is 2/5, found by dividing 42 and 105 by their greatest common factor, 21.
ILoveFractions, https://www.ilovefractions.com/tools/fraction-simplifier/42-105/, retrieved September 2, 2026

APA

ILoveFractions. (2026). 42/105 Simplified = 2/5. ILoveFractions.com. Retrieved September 2, 2026, from https://www.ilovefractions.com/tools/fraction-simplifier/42-105/

MLA

"42/105 Simplified = 2/5." ILoveFractions.com, https://www.ilovefractions.com/tools/fraction-simplifier/42-105/. Accessed 2 September 2026.

Need to simplify a different fraction?

Use the main fraction simplifier for any numerator and denominator.

Open the Fraction Simplifier