What is 1/54 plus 6/21? (Answer: 115/378)

Exact Answer

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Problem: What is 1/54 plus 6/21?
Formula / Expression: 1/54 + 6/21
Final Answer: 115/378
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 54 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 378 (which is smaller than their product 54 × 21 = 1134, keeping the calculation simpler).
Working: LCD(54, 21) = 378

Step 2: Convert to Equivalent Fractions with Common Denominator 378
Multiply the numerator and denominator of 1/54 by 7, and multiply the numerator and denominator of 6/21 by 18 so both fractions share the common base 378.
Working: 1 × 7/54 × 7 = 7/378 and 6 × 18/21 × 18 = 108/378

Step 3: Add the Numerators
Now add the numerators (7 + 108 = 115) and keep the common denominator 378 unchanged.
Working: 7 + 108/378 = 115/378

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 115 and 378 is 1, confirming that 115/378 cannot be reduced further—it is already in its simplest irreducible form.
Working: 115/378

Step 5: Decimal & Percentage Representation
Dividing the numerator 115 by denominator 378 produces a repeating decimal (approximately 0.304233, or 30.4233%).
Working: 115 ÷ 378 = 0.304233 (30.4233%)

Key Values:
- Simplified Fraction: 115/378
- Mixed Number Form: 115/378
- Decimal Value: 0.304233
- Percentage: 30.4233%

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Solved with FractionsCalc:
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1/54 + 6/21 = 115/378

Simplified Fraction

115/378

Mixed Number

Proper (115/378)

Decimal Value

0.304233

Percentage

30.4233%

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Step-by-Step Solution: 1/54 + 6/21

Step 1

Find the Least Common Denominator (LCD)

The denominators 54 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 378 (which is smaller than their product 54 × 21 = 1134, keeping the calculation simpler).

LCD(54, 21) = 378

Step 2

Convert to Equivalent Fractions with Common Denominator 378

Multiply the numerator and denominator of 1/54 by 7, and multiply the numerator and denominator of 6/21 by 18 so both fractions share the common base 378.

1 × 7/54 × 7 = 7/378 and 6 × 18/21 × 18 = 108/378

Step 3

Add the Numerators

Now add the numerators (7 + 108 = 115) and keep the common denominator 378 unchanged.

7 + 108/378 = 115/378

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 115 and 378 is 1, confirming that 115/378 cannot be reduced further—it is already in its simplest irreducible form.

115/378

Step 5

Decimal & Percentage Representation

Dividing the numerator 115 by denominator 378 produces a repeating decimal (approximately 0.304233, or 30.4233%).

115 ÷ 378 = 0.304233 (30.4233%)

Visual Representation

The diagram below illustrates 1/54 plus 6/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`115/378`
Mixed Number Form	`115/378`
Decimal Form	`0.304233`
Percentage	`30.4233%`

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Frequently Asked Questions

What is 1/54 plus 6/21 as a fraction?

1/54 + 6/21 in simplest fraction form is 115/378.

What is 1/54 plus 6/21 as a decimal?

1/54 + 6/21 converted to a decimal is 0.304233.

What is 1/54 plus 6/21 as a percentage?

1/54 + 6/21 expressed as a percentage is 30.4233%.

Does 1/54 plus 6/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.304233...) because the denominator contains prime factors other than 2 and 5.