What is 1/51 plus 3/21? (Answer: 58/357)

Exact Answer

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Problem: What is 1/51 plus 3/21?
Formula / Expression: 1/51 + 3/21
Final Answer: 58/357
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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 1/51 by 7, and multiply the numerator and denominator of 3/21 by 17 so both fractions share the common base 357.
Working: 1 × 7/51 × 7 = 7/357 and 3 × 17/21 × 17 = 51/357

Step 3: Add the Numerators
Now add the numerators (7 + 51 = 58) and keep the common denominator 357 unchanged.
Working: 7 + 51/357 = 58/357

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 58 and 357 is 1, confirming that 58/357 cannot be reduced further—it is already in its simplest irreducible form.
Working: 58/357

Step 5: Decimal & Percentage Representation
Dividing the numerator 58 by denominator 357 produces a repeating decimal (approximately 0.162465, or 16.2465%).
Working: 58 ÷ 357 = 0.162465 (16.2465%)

Key Values:
- Simplified Fraction: 58/357
- Mixed Number Form: 58/357
- Decimal Value: 0.162465
- Percentage: 16.2465%

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Solved with FractionsCalc:
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1/51 + 3/21 = 58/357

Simplified Fraction

58/357

Mixed Number

Proper (58/357)

Decimal Value

0.162465

Percentage

16.2465%

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Step-by-Step Solution: 1/51 + 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 1/51 by 7, and multiply the numerator and denominator of 3/21 by 17 so both fractions share the common base 357.

1 × 7/51 × 7 = 7/357 and 3 × 17/21 × 17 = 51/357

Step 3

Add the Numerators

Now add the numerators (7 + 51 = 58) and keep the common denominator 357 unchanged.

7 + 51/357 = 58/357

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 58 and 357 is 1, confirming that 58/357 cannot be reduced further—it is already in its simplest irreducible form.

58/357

Step 5

Decimal & Percentage Representation

Dividing the numerator 58 by denominator 357 produces a repeating decimal (approximately 0.162465, or 16.2465%).

58 ÷ 357 = 0.162465 (16.2465%)

Visual Representation

The diagram below illustrates 1/51 plus 3/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`58/357`
Mixed Number Form	`58/357`
Decimal Form	`0.162465`
Percentage	`16.2465%`

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Frequently Asked Questions

What is 1/51 plus 3/21 as a fraction?

1/51 + 3/21 in simplest fraction form is 58/357.

What is 1/51 plus 3/21 as a decimal?

1/51 + 3/21 converted to a decimal is 0.162465.

What is 1/51 plus 3/21 as a percentage?

1/51 + 3/21 expressed as a percentage is 16.2465%.

Does 1/51 plus 3/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.162465...) because the denominator contains prime factors other than 2 and 5.