What is 2/3 plus 9/13? (Answer: 53/39)

Exact Answer

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Problem: What is 2/3 plus 9/13?
Formula / Expression: 2/3 + 9/13
Final Answer: 1 14/39 (53/39)
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 3 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 3 × 13 = 39.
Working: LCD(3, 13) = 39

Step 2: Convert to Equivalent Fractions with Common Denominator 39
Multiply the numerator and denominator of 2/3 by 13, and multiply the numerator and denominator of 9/13 by 3 so both fractions share the common base 39.
Working: 2 × 13/3 × 13 = 26/39 and 9 × 3/13 × 3 = 27/39

Step 3: Add the Numerators
Now add the numerators (26 + 27 = 53) and keep the common denominator 39 unchanged.
Working: 26 + 27/39 = 53/39

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 53 and 39 is 1, confirming that 53/39 cannot be reduced further—it is already in its simplest irreducible form.
Working: 53/39

Step 5: Convert Improper Fraction to a Mixed Number
Since the numerator (53) is greater than the denominator (39), divide 53 by 39: it goes in 1 whole time(s) with a remainder of 14, giving the mixed number 1 14/39.
Working: 53/39 = 1 14/39

Step 6: Decimal & Percentage Representation
Dividing the numerator 53 by denominator 39 produces a repeating decimal (approximately 1.358974, or 135.8974%).
Working: 53 ÷ 39 = 1.358974 (135.8974%)

Key Values:
- Simplified Fraction: 53/39
- Mixed Number Form: 1 14/39
- Decimal Value: 1.358974
- Percentage: 135.8974%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-2-3-plus-9-13/
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2/3 + 9/13 = 53/39

Simplified Fraction

53/39

Mixed Number

1 14/39

Decimal Value

1.358974

Percentage

135.8974%

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Step-by-Step Solution: 2/3 + 9/13

Step 1

Find the Least Common Denominator (LCD)

The denominators 3 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 3 × 13 = 39.

LCD(3, 13) = 39

Step 2

Convert to Equivalent Fractions with Common Denominator 39

Multiply the numerator and denominator of 2/3 by 13, and multiply the numerator and denominator of 9/13 by 3 so both fractions share the common base 39.

2 × 13/3 × 13 = 26/39 and 9 × 3/13 × 3 = 27/39

Step 3

Add the Numerators

Now add the numerators (26 + 27 = 53) and keep the common denominator 39 unchanged.

26 + 27/39 = 53/39

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 53 and 39 is 1, confirming that 53/39 cannot be reduced further—it is already in its simplest irreducible form.

53/39

Step 5

Convert Improper Fraction to a Mixed Number

Since the numerator (53) is greater than the denominator (39), divide 53 by 39: it goes in 1 whole time(s) with a remainder of 14, giving the mixed number 1 14/39.

53/39 = 114/39

Step 6

Decimal & Percentage Representation

Dividing the numerator 53 by denominator 39 produces a repeating decimal (approximately 1.358974, or 135.8974%).

53 ÷ 39 = 1.358974 (135.8974%)

Visual Representation

The diagram below illustrates 2/3 plus 9/13 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`53/39`
Mixed Number Form	`1 14/39`
Decimal Form	`1.358974`
Percentage	`135.8974%`

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Frequently Asked Questions

What is 2/3 plus 9/13 as a fraction?

2/3 + 9/13 in simplest fraction form is 53/39 (or 1 14/39 as a mixed number).

What is 2/3 plus 9/13 as a decimal?

2/3 + 9/13 converted to a decimal is 1.358974.

What is 2/3 plus 9/13 as a percentage?

2/3 + 9/13 expressed as a percentage is 135.8974%.

How do you write 2/3 plus 9/13 as a mixed number?

Because the numerator is greater than the denominator, the improper fraction 53/39 can be written as the mixed number 1 14/39.

Does 2/3 plus 9/13 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 1.358974...) because the denominator contains prime factors other than 2 and 5.