What is 2/51 plus 3/21? (Answer: 65/357)

Exact Answer

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Problem: What is 2/51 plus 3/21?
Formula / Expression: 2/51 + 3/21
Final Answer: 65/357
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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 2/51 by 7, and multiply the numerator and denominator of 3/21 by 17 so both fractions share the common base 357.
Working: 2 × 7/51 × 7 = 14/357 and 3 × 17/21 × 17 = 51/357

Step 3: Add the Numerators
Now add the numerators (14 + 51 = 65) and keep the common denominator 357 unchanged.
Working: 14 + 51/357 = 65/357

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 65 and 357 is 1, confirming that 65/357 cannot be reduced further—it is already in its simplest irreducible form.
Working: 65/357

Step 5: Decimal & Percentage Representation
Dividing the numerator 65 by denominator 357 produces a repeating decimal (approximately 0.182073, or 18.2073%).
Working: 65 ÷ 357 = 0.182073 (18.2073%)

Key Values:
- Simplified Fraction: 65/357
- Mixed Number Form: 65/357
- Decimal Value: 0.182073
- Percentage: 18.2073%

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Solved with FractionsCalc:
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2/51 + 3/21 = 65/357

Simplified Fraction

65/357

Mixed Number

Proper (65/357)

Decimal Value

0.182073

Percentage

18.2073%

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Step-by-Step Solution: 2/51 + 3/21

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 2/51 by 7, and multiply the numerator and denominator of 3/21 by 17 so both fractions share the common base 357.

2 × 7/51 × 7 = 14/357 and 3 × 17/21 × 17 = 51/357

Step 3

Add the Numerators

Now add the numerators (14 + 51 = 65) and keep the common denominator 357 unchanged.

14 + 51/357 = 65/357

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 65 and 357 is 1, confirming that 65/357 cannot be reduced further—it is already in its simplest irreducible form.

65/357

Step 5

Decimal & Percentage Representation

Dividing the numerator 65 by denominator 357 produces a repeating decimal (approximately 0.182073, or 18.2073%).

65 ÷ 357 = 0.182073 (18.2073%)

Visual Representation

The diagram below illustrates 2/51 plus 3/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`65/357`
Mixed Number Form	`65/357`
Decimal Form	`0.182073`
Percentage	`18.2073%`

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Frequently Asked Questions

What is 2/51 plus 3/21 as a fraction?

2/51 + 3/21 in simplest fraction form is 65/357.

What is 2/51 plus 3/21 as a decimal?

2/51 + 3/21 converted to a decimal is 0.182073.

What is 2/51 plus 3/21 as a percentage?

2/51 + 3/21 expressed as a percentage is 18.2073%.

Does 2/51 plus 3/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.182073...) because the denominator contains prime factors other than 2 and 5.