18/21 Simplified
The fraction 18/21 written in its simplest form.
18/21 in simplest form
6/7
= 0.857143 as a decimal · 85.7143% as a percentage
How it works
To reduce a fraction, divide the numerator and denominator by their greatest common factor (GCF).
- GCF of 18 and 21 = 3
- 18 ÷ 3 = 6
- 21 ÷ 3 = 7
So 18/21 = 6/7, which cannot be reduced further because 6 and 7 share no common factor other than 1.
Equivalent fractions
18/21 = 6/7 = 12/14 = 18/21 = 24/28 — all equal to 0.857143.
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Frequently asked questions
What is 18/21 in simplest form?+
18/21 simplifies to 6/7. Both the numerator and denominator share a greatest common factor of 3, and dividing each by 3 gives 6/7.
How do you simplify 18/21?+
Find the greatest common factor (GCF) of 18 and 21, which is 3, then divide the top and bottom by it: 18 ÷ 3 = 6 and 21 ÷ 3 = 7, giving 6/7.