What is 6/9 plus 11/13? (Answer: 59/39)

Exact Answer

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Problem: What is 6/9 plus 11/13?
Formula / Expression: 6/9 + 11/13
Final Answer: 1 20/39 (59/39)
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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 6/9 by 13, and multiply the numerator and denominator of 11/13 by 9 so both fractions share the common base 117.
Working: 6 × 13/9 × 13 = 78/117 and 11 × 9/13 × 9 = 99/117

Step 3: Add the Numerators
Now add the numerators (78 + 99 = 177) and keep the common denominator 117 unchanged.
Working: 78 + 99/117 = 177/117

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 177 and 117, which is 3. Divide both the numerator and denominator by 3.
Working: 177 ÷ 3/117 ÷ 3 = 59/39

Step 5: Convert Improper Fraction to a Mixed Number
Since the numerator (59) is greater than the denominator (39), divide 59 by 39: it goes in 1 whole time(s) with a remainder of 20, giving the mixed number 1 20/39.
Working: 59/39 = 1 20/39

Step 6: Decimal & Percentage Representation
Dividing the numerator 59 by denominator 39 produces a repeating decimal (approximately 1.512821, or 151.2821%).
Working: 59 ÷ 39 = 1.512821 (151.2821%)

Key Values:
- Simplified Fraction: 59/39
- Mixed Number Form: 1 20/39
- Decimal Value: 1.512821
- Percentage: 151.2821%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-6-9-plus-11-13/
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6/9 + 11/13 = 59/39

Simplified Fraction

59/39

Mixed Number

1 20/39

Decimal Value

1.512821

Percentage

151.2821%

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Step-by-Step Solution: 6/9 + 11/13

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 6/9 by 13, and multiply the numerator and denominator of 11/13 by 9 so both fractions share the common base 117.

6 × 13/9 × 13 = 78/117 and 11 × 9/13 × 9 = 99/117

Step 3

Add the Numerators

Now add the numerators (78 + 99 = 177) and keep the common denominator 117 unchanged.

78 + 99/117 = 177/117

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 177 and 117, which is 3. Divide both the numerator and denominator by 3.

177 ÷ 3/117 ÷ 3 = 59/39

Step 5

Convert Improper Fraction to a Mixed Number

Since the numerator (59) is greater than the denominator (39), divide 59 by 39: it goes in 1 whole time(s) with a remainder of 20, giving the mixed number 1 20/39.

59/39 = 120/39

Step 6

Decimal & Percentage Representation

Dividing the numerator 59 by denominator 39 produces a repeating decimal (approximately 1.512821, or 151.2821%).

59 ÷ 39 = 1.512821 (151.2821%)

Visual Representation

The diagram below illustrates 6/9 plus 11/13 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`59/39`
Mixed Number Form	`1 20/39`
Decimal Form	`1.512821`
Percentage	`151.2821%`

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Frequently Asked Questions

What is 6/9 plus 11/13 as a fraction?

6/9 + 11/13 in simplest fraction form is 59/39 (or 1 20/39 as a mixed number).

What is 6/9 plus 11/13 as a decimal?

6/9 + 11/13 converted to a decimal is 1.512821.

What is 6/9 plus 11/13 as a percentage?

6/9 + 11/13 expressed as a percentage is 151.2821%.

How do you write 6/9 plus 11/13 as a mixed number?

Because the numerator is greater than the denominator, the improper fraction 59/39 can be written as the mixed number 1 20/39.

Does 6/9 plus 11/13 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 1.512821...) because the denominator contains prime factors other than 2 and 5.