What is 7/21 plus 10/21?
7/21 plus 10/21 equals 17/21 (or 0.809524 in decimal form). Learn the step-by-step solution to add 7/21 and 10/21 using Least Common Denominator and simplification.
Exact Answer
7/21 + 10/21 = 17/21
Simplified Fraction
17/21
Mixed Number
Proper (17/21)
Decimal Value
0.809524
Percentage
80.9524%
Step-by-Step Solution: 7/21 + 10/21
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.
7/21 + 10/21
Step 2
Add the Numerators
Now add the numerators (7 + 10 = 17) and keep the common denominator 21 unchanged.
7 + 10/21 = 17/21
Step 3
Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 17 and 21 is 1, confirming that 17/21 cannot be reduced further—it is already in its simplest irreducible form.
17/21
Step 4
Decimal & Percentage Representation
Dividing the numerator 17 by denominator 21 produces a repeating decimal (approximately 0.809524, or 80.9524%).
17 ÷ 21 = 0.809524 (80.9524%)
Visual Representation
The diagram below illustrates 7/21 plus 10/21 visually:
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Summary & Alternative Representations
| Property / Format | Value |
|---|---|
| Lowest Terms Fraction | 17/21 |
| Mixed Number Form | 17/21 |
| Decimal Form | 0.809524 |
| Percentage | 80.9524% |
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Frequently Asked Questions
What is 7/21 plus 10/21 as a fraction?
7/21 + 10/21 in simplest fraction form is 17/21.
What is 7/21 plus 10/21 as a decimal?
7/21 + 10/21 converted to a decimal is 0.809524.
What is 7/21 plus 10/21 as a percentage?
7/21 + 10/21 expressed as a percentage is 80.9524%.
Does 7/21 plus 10/21 result in a terminating or repeating decimal?
It results in a repeating decimal (approximately 0.809524...) because the denominator contains prime factors other than 2 and 5.