What is 7/12 plus 11/13? (Answer: 223/156)

Exact Answer

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Problem: What is 7/12 plus 11/13?
Formula / Expression: 7/12 + 11/13
Final Answer: 1 67/156 (223/156)
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 12 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 12 × 13 = 156.
Working: LCD(12, 13) = 156

Step 2: Convert to Equivalent Fractions with Common Denominator 156
Multiply the numerator and denominator of 7/12 by 13, and multiply the numerator and denominator of 11/13 by 12 so both fractions share the common base 156.
Working: 7 × 13/12 × 13 = 91/156 and 11 × 12/13 × 12 = 132/156

Step 3: Add the Numerators
Now add the numerators (91 + 132 = 223) and keep the common denominator 156 unchanged.
Working: 91 + 132/156 = 223/156

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 223 and 156 is 1, confirming that 223/156 cannot be reduced further—it is already in its simplest irreducible form.
Working: 223/156

Step 5: Convert Improper Fraction to a Mixed Number
Since the numerator (223) is greater than the denominator (156), divide 223 by 156: it goes in 1 whole time(s) with a remainder of 67, giving the mixed number 1 67/156.
Working: 223/156 = 1 67/156

Step 6: Decimal & Percentage Representation
Dividing the numerator 223 by denominator 156 produces a repeating decimal (approximately 1.429487, or 142.9487%).
Working: 223 ÷ 156 = 1.429487 (142.9487%)

Key Values:
- Simplified Fraction: 223/156
- Mixed Number Form: 1 67/156
- Decimal Value: 1.429487
- Percentage: 142.9487%

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Solved with FractionsCalc:
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7/12 + 11/13 = 223/156

Simplified Fraction

223/156

Mixed Number

1 67/156

Decimal Value

1.429487

Percentage

142.9487%

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Step-by-Step Solution: 7/12 + 11/13

Step 1

Find the Least Common Denominator (LCD)

The denominators 12 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 12 × 13 = 156.

LCD(12, 13) = 156

Step 2

Convert to Equivalent Fractions with Common Denominator 156

Multiply the numerator and denominator of 7/12 by 13, and multiply the numerator and denominator of 11/13 by 12 so both fractions share the common base 156.

7 × 13/12 × 13 = 91/156 and 11 × 12/13 × 12 = 132/156

Step 3

Add the Numerators

Now add the numerators (91 + 132 = 223) and keep the common denominator 156 unchanged.

91 + 132/156 = 223/156

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 223 and 156 is 1, confirming that 223/156 cannot be reduced further—it is already in its simplest irreducible form.

223/156

Step 5

Convert Improper Fraction to a Mixed Number

Since the numerator (223) is greater than the denominator (156), divide 223 by 156: it goes in 1 whole time(s) with a remainder of 67, giving the mixed number 1 67/156.

223/156 = 167/156

Step 6

Decimal & Percentage Representation

Dividing the numerator 223 by denominator 156 produces a repeating decimal (approximately 1.429487, or 142.9487%).

223 ÷ 156 = 1.429487 (142.9487%)

Visual Representation

The diagram below illustrates 7/12 plus 11/13 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`223/156`
Mixed Number Form	`1 67/156`
Decimal Form	`1.429487`
Percentage	`142.9487%`

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Frequently Asked Questions

What is 7/12 plus 11/13 as a fraction?

7/12 + 11/13 in simplest fraction form is 223/156 (or 1 67/156 as a mixed number).

What is 7/12 plus 11/13 as a decimal?

7/12 + 11/13 converted to a decimal is 1.429487.

What is 7/12 plus 11/13 as a percentage?

7/12 + 11/13 expressed as a percentage is 142.9487%.

How do you write 7/12 plus 11/13 as a mixed number?

Because the numerator is greater than the denominator, the improper fraction 223/156 can be written as the mixed number 1 67/156.

Does 7/12 plus 11/13 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 1.429487...) because the denominator contains prime factors other than 2 and 5.