Simplest form answer

18/45 Simplified = 2/5

18/45 in simplest form is 2/5, found by dividing 18 and 45 by their greatest common factor, 9. 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 18 and 45 is 9.

2. Divide the numerator and denominator by the GCF.

18 ÷ 9 = 2

45 ÷ 9 = 5

3. Write the result.

18/45 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

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18/45 in simplest form is 2/5, found by dividing 18 and 45 by their greatest common factor, 9.
ILoveFractions, https://www.ilovefractions.com/tools/fraction-simplifier/18-45/, retrieved September 2, 2026

APA

ILoveFractions. (2026). 18/45 Simplified = 2/5. ILoveFractions.com. Retrieved September 2, 2026, from https://www.ilovefractions.com/tools/fraction-simplifier/18-45/

MLA

"18/45 Simplified = 2/5." ILoveFractions.com, https://www.ilovefractions.com/tools/fraction-simplifier/18-45/. Accessed 2 September 2026.

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