What is 4/7 plus 11/13? (Answer: 129/91)

Exact Answer

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Problem: What is 4/7 plus 11/13?
Formula / Expression: 4/7 + 11/13
Final Answer: 1 38/91 (129/91)
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 7 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 7 × 13 = 91.
Working: LCD(7, 13) = 91

Step 2: Convert to Equivalent Fractions with Common Denominator 91
Multiply the numerator and denominator of 4/7 by 13, and multiply the numerator and denominator of 11/13 by 7 so both fractions share the common base 91.
Working: 4 × 13/7 × 13 = 52/91 and 11 × 7/13 × 7 = 77/91

Step 3: Add the Numerators
Now add the numerators (52 + 77 = 129) and keep the common denominator 91 unchanged.
Working: 52 + 77/91 = 129/91

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 129 and 91 is 1, confirming that 129/91 cannot be reduced further—it is already in its simplest irreducible form.
Working: 129/91

Step 5: Convert Improper Fraction to a Mixed Number
Since the numerator (129) is greater than the denominator (91), divide 129 by 91: it goes in 1 whole time(s) with a remainder of 38, giving the mixed number 1 38/91.
Working: 129/91 = 1 38/91

Step 6: Decimal & Percentage Representation
Dividing the numerator 129 by denominator 91 produces a repeating decimal (approximately 1.417582, or 141.7582%).
Working: 129 ÷ 91 = 1.417582 (141.7582%)

Key Values:
- Simplified Fraction: 129/91
- Mixed Number Form: 1 38/91
- Decimal Value: 1.417582
- Percentage: 141.7582%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-4-7-plus-11-13/
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4/7 + 11/13 = 129/91

Simplified Fraction

129/91

Mixed Number

1 38/91

Decimal Value

1.417582

Percentage

141.7582%

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Step-by-Step Solution: 4/7 + 11/13

Step 1

Find the Least Common Denominator (LCD)

The denominators 7 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 7 × 13 = 91.

LCD(7, 13) = 91

Step 2

Convert to Equivalent Fractions with Common Denominator 91

Multiply the numerator and denominator of 4/7 by 13, and multiply the numerator and denominator of 11/13 by 7 so both fractions share the common base 91.

4 × 13/7 × 13 = 52/91 and 11 × 7/13 × 7 = 77/91

Step 3

Add the Numerators

Now add the numerators (52 + 77 = 129) and keep the common denominator 91 unchanged.

52 + 77/91 = 129/91

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 129 and 91 is 1, confirming that 129/91 cannot be reduced further—it is already in its simplest irreducible form.

129/91

Step 5

Convert Improper Fraction to a Mixed Number

Since the numerator (129) is greater than the denominator (91), divide 129 by 91: it goes in 1 whole time(s) with a remainder of 38, giving the mixed number 1 38/91.

129/91 = 138/91

Step 6

Decimal & Percentage Representation

Dividing the numerator 129 by denominator 91 produces a repeating decimal (approximately 1.417582, or 141.7582%).

129 ÷ 91 = 1.417582 (141.7582%)

Visual Representation

The diagram below illustrates 4/7 plus 11/13 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`129/91`
Mixed Number Form	`1 38/91`
Decimal Form	`1.417582`
Percentage	`141.7582%`

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Frequently Asked Questions

What is 4/7 plus 11/13 as a fraction?

4/7 + 11/13 in simplest fraction form is 129/91 (or 1 38/91 as a mixed number).

What is 4/7 plus 11/13 as a decimal?

4/7 + 11/13 converted to a decimal is 1.417582.

What is 4/7 plus 11/13 as a percentage?

4/7 + 11/13 expressed as a percentage is 141.7582%.

How do you write 4/7 plus 11/13 as a mixed number?

Because the numerator is greater than the denominator, the improper fraction 129/91 can be written as the mixed number 1 38/91.

Does 4/7 plus 11/13 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 1.417582...) because the denominator contains prime factors other than 2 and 5.