What is 6/21 plus 9/21?
6/21 plus 9/21 equals 5/7 (or 0.714286 in decimal form). Learn the step-by-step solution to add 6/21 and 9/21 using Least Common Denominator and simplification.
Exact Answer
6/21 + 9/21 = 5/7
Simplified Fraction
5/7
Mixed Number
Proper (5/7)
Decimal Value
0.714286
Percentage
71.4286%
Step-by-Step Solution: 6/21 + 9/21
Step 1
Check the Denominators (Like Fractions)
Both fractions already share the identical denominator (21). Because these are like fractions, no conversion to a common denominator is required—we directly add their numerators while keeping the denominator 21.
6/21 + 9/21
Step 2
Add the Numerators
Now add the numerators (6 + 9 = 15) and keep the common denominator 21 unchanged.
6 + 9/21 = 15/21
Step 3
Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 15 and 21, which is 3. Divide both the numerator and denominator by 3.
15 ÷ 3/21 ÷ 3 = 5/7
Step 4
Decimal & Percentage Representation
Dividing the numerator 5 by denominator 7 produces a repeating decimal (approximately 0.714286, or 71.4286%).
5 ÷ 7 = 0.714286 (71.4286%)
Visual Representation
The diagram below illustrates 6/21 plus 9/21 visually:
+
=
Summary & Alternative Representations
| Property / Format | Value |
|---|---|
| Lowest Terms Fraction | 5/7 |
| Mixed Number Form | 5/7 |
| Decimal Form | 0.714286 |
| Percentage | 71.4286% |
Was this solution helpful?
Help us improve our free step-by-step tools
Frequently Asked Questions
What is 6/21 plus 9/21 as a fraction?
6/21 + 9/21 in simplest fraction form is 5/7.
What is 6/21 plus 9/21 as a decimal?
6/21 + 9/21 converted to a decimal is 0.714286.
What is 6/21 plus 9/21 as a percentage?
6/21 + 9/21 expressed as a percentage is 71.4286%.
Does 6/21 plus 9/21 result in a terminating or repeating decimal?
It results in a repeating decimal (approximately 0.714286...) because the denominator contains prime factors other than 2 and 5.