What is 12/25 plus 9/13? (Answer: 381/325)

Exact Answer

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Problem: What is 12/25 plus 9/13?
Formula / Expression: 12/25 + 9/13
Final Answer: 1 56/325 (381/325)
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 25 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 25 × 13 = 325.
Working: LCD(25, 13) = 325

Step 2: Convert to Equivalent Fractions with Common Denominator 325
Multiply the numerator and denominator of 12/25 by 13, and multiply the numerator and denominator of 9/13 by 25 so both fractions share the common base 325.
Working: 12 × 13/25 × 13 = 156/325 and 9 × 25/13 × 25 = 225/325

Step 3: Add the Numerators
Now add the numerators (156 + 225 = 381) and keep the common denominator 325 unchanged.
Working: 156 + 225/325 = 381/325

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 381 and 325 is 1, confirming that 381/325 cannot be reduced further—it is already in its simplest irreducible form.
Working: 381/325

Step 5: Convert Improper Fraction to a Mixed Number
Since the numerator (381) is greater than the denominator (325), divide 381 by 325: it goes in 1 whole time(s) with a remainder of 56, giving the mixed number 1 56/325.
Working: 381/325 = 1 56/325

Step 6: Decimal & Percentage Representation
Dividing the numerator 381 by denominator 325 produces a repeating decimal (approximately 1.172308, or 117.2308%).
Working: 381 ÷ 325 = 1.172308 (117.2308%)

Key Values:
- Simplified Fraction: 381/325
- Mixed Number Form: 1 56/325
- Decimal Value: 1.172308
- Percentage: 117.2308%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-12-25-plus-9-13/
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12/25 + 9/13 = 381/325

Simplified Fraction

381/325

Mixed Number

1 56/325

Decimal Value

1.172308

Percentage

117.2308%

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Step-by-Step Solution: 12/25 + 9/13

Step 1

Find the Least Common Denominator (LCD)

The denominators 25 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 25 × 13 = 325.

LCD(25, 13) = 325

Step 2

Convert to Equivalent Fractions with Common Denominator 325

Multiply the numerator and denominator of 12/25 by 13, and multiply the numerator and denominator of 9/13 by 25 so both fractions share the common base 325.

12 × 13/25 × 13 = 156/325 and 9 × 25/13 × 25 = 225/325

Step 3

Add the Numerators

Now add the numerators (156 + 225 = 381) and keep the common denominator 325 unchanged.

156 + 225/325 = 381/325

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 381 and 325 is 1, confirming that 381/325 cannot be reduced further—it is already in its simplest irreducible form.

381/325

Step 5

Convert Improper Fraction to a Mixed Number

Since the numerator (381) is greater than the denominator (325), divide 381 by 325: it goes in 1 whole time(s) with a remainder of 56, giving the mixed number 1 56/325.

381/325 = 156/325

Step 6

Decimal & Percentage Representation

Dividing the numerator 381 by denominator 325 produces a repeating decimal (approximately 1.172308, or 117.2308%).

381 ÷ 325 = 1.172308 (117.2308%)

Visual Representation

The diagram below illustrates 12/25 plus 9/13 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`381/325`
Mixed Number Form	`1 56/325`
Decimal Form	`1.172308`
Percentage	`117.2308%`

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Frequently Asked Questions

What is 12/25 plus 9/13 as a fraction?

12/25 + 9/13 in simplest fraction form is 381/325 (or 1 56/325 as a mixed number).

What is 12/25 plus 9/13 as a decimal?

12/25 + 9/13 converted to a decimal is 1.172308.

What is 12/25 plus 9/13 as a percentage?

12/25 + 9/13 expressed as a percentage is 117.2308%.

How do you write 12/25 plus 9/13 as a mixed number?

Because the numerator is greater than the denominator, the improper fraction 381/325 can be written as the mixed number 1 56/325.

Does 12/25 plus 9/13 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 1.172308...) because the denominator contains prime factors other than 2 and 5.