What is 5/9 plus 8/13? (Answer: 137/117)

Exact Answer

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Problem: What is 5/9 plus 8/13?
Formula / Expression: 5/9 + 8/13
Final Answer: 1 20/117 (137/117)
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 9 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 9 × 13 = 117.
Working: LCD(9, 13) = 117

Step 2: Convert to Equivalent Fractions with Common Denominator 117
Multiply the numerator and denominator of 5/9 by 13, and multiply the numerator and denominator of 8/13 by 9 so both fractions share the common base 117.
Working: 5 × 13/9 × 13 = 65/117 and 8 × 9/13 × 9 = 72/117

Step 3: Add the Numerators
Now add the numerators (65 + 72 = 137) and keep the common denominator 117 unchanged.
Working: 65 + 72/117 = 137/117

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 137 and 117 is 1, confirming that 137/117 cannot be reduced further—it is already in its simplest irreducible form.
Working: 137/117

Step 5: Convert Improper Fraction to a Mixed Number
Since the numerator (137) is greater than the denominator (117), divide 137 by 117: it goes in 1 whole time(s) with a remainder of 20, giving the mixed number 1 20/117.
Working: 137/117 = 1 20/117

Step 6: Decimal & Percentage Representation
Dividing the numerator 137 by denominator 117 produces a repeating decimal (approximately 1.17094, or 117.094%).
Working: 137 ÷ 117 = 1.17094 (117.094%)

Key Values:
- Simplified Fraction: 137/117
- Mixed Number Form: 1 20/117
- Decimal Value: 1.17094
- Percentage: 117.094%

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Solved with FractionsCalc:
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5/9 + 8/13 = 137/117

Simplified Fraction

137/117

Mixed Number

1 20/117

Decimal Value

1.17094

Percentage

117.094%

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Step-by-Step Solution: 5/9 + 8/13

Step 1

Find the Least Common Denominator (LCD)

The denominators 9 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 9 × 13 = 117.

LCD(9, 13) = 117

Step 2

Convert to Equivalent Fractions with Common Denominator 117

Multiply the numerator and denominator of 5/9 by 13, and multiply the numerator and denominator of 8/13 by 9 so both fractions share the common base 117.

5 × 13/9 × 13 = 65/117 and 8 × 9/13 × 9 = 72/117

Step 3

Add the Numerators

Now add the numerators (65 + 72 = 137) and keep the common denominator 117 unchanged.

65 + 72/117 = 137/117

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 137 and 117 is 1, confirming that 137/117 cannot be reduced further—it is already in its simplest irreducible form.

137/117

Step 5

Convert Improper Fraction to a Mixed Number

Since the numerator (137) is greater than the denominator (117), divide 137 by 117: it goes in 1 whole time(s) with a remainder of 20, giving the mixed number 1 20/117.

137/117 = 120/117

Step 6

Decimal & Percentage Representation

Dividing the numerator 137 by denominator 117 produces a repeating decimal (approximately 1.17094, or 117.094%).

137 ÷ 117 = 1.17094 (117.094%)

Visual Representation

The diagram below illustrates 5/9 plus 8/13 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`137/117`
Mixed Number Form	`1 20/117`
Decimal Form	`1.17094`
Percentage	`117.094%`

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Frequently Asked Questions

What is 5/9 plus 8/13 as a fraction?

5/9 + 8/13 in simplest fraction form is 137/117 (or 1 20/117 as a mixed number).

What is 5/9 plus 8/13 as a decimal?

5/9 + 8/13 converted to a decimal is 1.17094.

What is 5/9 plus 8/13 as a percentage?

5/9 + 8/13 expressed as a percentage is 117.094%.

How do you write 5/9 plus 8/13 as a mixed number?

Because the numerator is greater than the denominator, the improper fraction 137/117 can be written as the mixed number 1 20/117.

Does 5/9 plus 8/13 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 1.17094...) because the denominator contains prime factors other than 2 and 5.