What is 6/51 plus 8/21? (Answer: 178/357)

Exact Answer

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Problem: What is 6/51 plus 8/21?
Formula / Expression: 6/51 + 8/21
Final Answer: 178/357
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 51 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 357 (which is smaller than their product 51 × 21 = 1071, keeping the calculation simpler).
Working: LCD(51, 21) = 357

Step 2: Convert to Equivalent Fractions with Common Denominator 357
Multiply the numerator and denominator of 6/51 by 7, and multiply the numerator and denominator of 8/21 by 17 so both fractions share the common base 357.
Working: 6 × 7/51 × 7 = 42/357 and 8 × 17/21 × 17 = 136/357

Step 3: Add the Numerators
Now add the numerators (42 + 136 = 178) and keep the common denominator 357 unchanged.
Working: 42 + 136/357 = 178/357

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 178 and 357 is 1, confirming that 178/357 cannot be reduced further—it is already in its simplest irreducible form.
Working: 178/357

Step 5: Decimal & Percentage Representation
Dividing the numerator 178 by denominator 357 produces a repeating decimal (approximately 0.498599, or 49.8599%).
Working: 178 ÷ 357 = 0.498599 (49.8599%)

Key Values:
- Simplified Fraction: 178/357
- Mixed Number Form: 178/357
- Decimal Value: 0.498599
- Percentage: 49.8599%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-6-51-plus-8-21/
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6/51 + 8/21 = 178/357

Simplified Fraction

178/357

Mixed Number

Proper (178/357)

Decimal Value

0.498599

Percentage

49.8599%

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Step-by-Step Solution: 6/51 + 8/21

Step 1

Find the Least Common Denominator (LCD)

The denominators 51 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 357 (which is smaller than their product 51 × 21 = 1071, keeping the calculation simpler).

LCD(51, 21) = 357

Step 2

Convert to Equivalent Fractions with Common Denominator 357

Multiply the numerator and denominator of 6/51 by 7, and multiply the numerator and denominator of 8/21 by 17 so both fractions share the common base 357.

6 × 7/51 × 7 = 42/357 and 8 × 17/21 × 17 = 136/357

Step 3

Add the Numerators

Now add the numerators (42 + 136 = 178) and keep the common denominator 357 unchanged.

42 + 136/357 = 178/357

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 178 and 357 is 1, confirming that 178/357 cannot be reduced further—it is already in its simplest irreducible form.

178/357

Step 5

Decimal & Percentage Representation

Dividing the numerator 178 by denominator 357 produces a repeating decimal (approximately 0.498599, or 49.8599%).

178 ÷ 357 = 0.498599 (49.8599%)

Visual Representation

The diagram below illustrates 6/51 plus 8/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`178/357`
Mixed Number Form	`178/357`
Decimal Form	`0.498599`
Percentage	`49.8599%`

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Frequently Asked Questions

What is 6/51 plus 8/21 as a fraction?

6/51 + 8/21 in simplest fraction form is 178/357.

What is 6/51 plus 8/21 as a decimal?

6/51 + 8/21 converted to a decimal is 0.498599.

What is 6/51 plus 8/21 as a percentage?

6/51 + 8/21 expressed as a percentage is 49.8599%.

Does 6/51 plus 8/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.498599...) because the denominator contains prime factors other than 2 and 5.