What is 10/55 plus 10/21? (Answer: 152/231)

Exact Answer

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Problem: What is 10/55 plus 10/21?
Formula / Expression: 10/55 + 10/21
Final Answer: 152/231
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 55 and 21 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 55 × 21 = 1155.
Working: LCD(55, 21) = 1155

Step 2: Convert to Equivalent Fractions with Common Denominator 1155
Multiply the numerator and denominator of 10/55 by 21, and multiply the numerator and denominator of 10/21 by 55 so both fractions share the common base 1155.
Working: 10 × 21/55 × 21 = 210/1155 and 10 × 55/21 × 55 = 550/1155

Step 3: Add the Numerators
Now add the numerators (210 + 550 = 760) and keep the common denominator 1155 unchanged.
Working: 210 + 550/1155 = 760/1155

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 760 and 1155, which is 5. Divide both the numerator and denominator by 5.
Working: 760 ÷ 5/1155 ÷ 5 = 152/231

Step 5: Decimal & Percentage Representation
Dividing the numerator 152 by denominator 231 produces a repeating decimal (approximately 0.658009, or 65.8009%).
Working: 152 ÷ 231 = 0.658009 (65.8009%)

Key Values:
- Simplified Fraction: 152/231
- Mixed Number Form: 152/231
- Decimal Value: 0.658009
- Percentage: 65.8009%

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Solved with FractionsCalc:
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10/55 + 10/21 = 152/231

Simplified Fraction

152/231

Mixed Number

Proper (152/231)

Decimal Value

0.658009

Percentage

65.8009%

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Step-by-Step Solution: 10/55 + 10/21

Step 1

Find the Least Common Denominator (LCD)

The denominators 55 and 21 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 55 × 21 = 1155.

LCD(55, 21) = 1155

Step 2

Convert to Equivalent Fractions with Common Denominator 1155

Multiply the numerator and denominator of 10/55 by 21, and multiply the numerator and denominator of 10/21 by 55 so both fractions share the common base 1155.

10 × 21/55 × 21 = 210/1155 and 10 × 55/21 × 55 = 550/1155

Step 3

Add the Numerators

Now add the numerators (210 + 550 = 760) and keep the common denominator 1155 unchanged.

210 + 550/1155 = 760/1155

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 760 and 1155, which is 5. Divide both the numerator and denominator by 5.

760 ÷ 5/1155 ÷ 5 = 152/231

Step 5

Decimal & Percentage Representation

Dividing the numerator 152 by denominator 231 produces a repeating decimal (approximately 0.658009, or 65.8009%).

152 ÷ 231 = 0.658009 (65.8009%)

Visual Representation

The diagram below illustrates 10/55 plus 10/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`152/231`
Mixed Number Form	`152/231`
Decimal Form	`0.658009`
Percentage	`65.8009%`

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Frequently Asked Questions

What is 10/55 plus 10/21 as a fraction?

10/55 + 10/21 in simplest fraction form is 152/231.

What is 10/55 plus 10/21 as a decimal?

10/55 + 10/21 converted to a decimal is 0.658009.

What is 10/55 plus 10/21 as a percentage?

10/55 + 10/21 expressed as a percentage is 65.8009%.

Does 10/55 plus 10/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.658009...) because the denominator contains prime factors other than 2 and 5.