The simplest form of 9/21 is 3/7.
Steps to simplifying fractions
- Find the GCD (or HCF) of numerator and denominator
GCD of 9 and 21 is 3 - Divide both the numerator and denominator by the GCD
9 ÷ 3/21 ÷ 3 - Reduced fraction: 3/7
Therefore, 9/21 simplified to lowest terms is 3/7.
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Equivalent fractions: 18/42 27/63 3/7 45/105 63/147
More fractions: 18/21 9/42 27/21 9/63 10/21 9/228/21 9/20