The simplest form of 21/7 is 3/1.
Steps to simplifying fractions
- Find the GCD (or HCF) of numerator and denominator
GCD of 21 and 7 is 7 - Divide both the numerator and denominator by the GCD
21 ÷ 7/7 ÷ 7 - Reduced fraction: 3/1
Therefore, 21/7 simplified to lowest terms is 3/1.
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Equivalent fractions: 42/14 63/21 105/35 147/49 3/1
More fractions: 42/7 21/14 63/7 21/21 22/7 21/820/7 21/6