What is 11/16 plus 9/13? (Answer: 287/208)

Exact Answer

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Problem: What is 11/16 plus 9/13?
Formula / Expression: 11/16 + 9/13
Final Answer: 1 79/208 (287/208)
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 16 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 16 × 13 = 208.
Working: LCD(16, 13) = 208

Step 2: Convert to Equivalent Fractions with Common Denominator 208
Multiply the numerator and denominator of 11/16 by 13, and multiply the numerator and denominator of 9/13 by 16 so both fractions share the common base 208.
Working: 11 × 13/16 × 13 = 143/208 and 9 × 16/13 × 16 = 144/208

Step 3: Add the Numerators
Now add the numerators (143 + 144 = 287) and keep the common denominator 208 unchanged.
Working: 143 + 144/208 = 287/208

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 287 and 208 is 1, confirming that 287/208 cannot be reduced further—it is already in its simplest irreducible form.
Working: 287/208

Step 5: Convert Improper Fraction to a Mixed Number
Since the numerator (287) is greater than the denominator (208), divide 287 by 208: it goes in 1 whole time(s) with a remainder of 79, giving the mixed number 1 79/208.
Working: 287/208 = 1 79/208

Step 6: Decimal & Percentage Representation
Dividing the numerator 287 by denominator 208 produces a repeating decimal (approximately 1.379808, or 137.9808%).
Working: 287 ÷ 208 = 1.379808 (137.9808%)

Key Values:
- Simplified Fraction: 287/208
- Mixed Number Form: 1 79/208
- Decimal Value: 1.379808
- Percentage: 137.9808%

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Solved with FractionsCalc:
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11/16 + 9/13 = 287/208

Simplified Fraction

287/208

Mixed Number

1 79/208

Decimal Value

1.379808

Percentage

137.9808%

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Step-by-Step Solution: 11/16 + 9/13

Step 1

Find the Least Common Denominator (LCD)

The denominators 16 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 16 × 13 = 208.

LCD(16, 13) = 208

Step 2

Convert to Equivalent Fractions with Common Denominator 208

Multiply the numerator and denominator of 11/16 by 13, and multiply the numerator and denominator of 9/13 by 16 so both fractions share the common base 208.

11 × 13/16 × 13 = 143/208 and 9 × 16/13 × 16 = 144/208

Step 3

Add the Numerators

Now add the numerators (143 + 144 = 287) and keep the common denominator 208 unchanged.

143 + 144/208 = 287/208

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 287 and 208 is 1, confirming that 287/208 cannot be reduced further—it is already in its simplest irreducible form.

287/208

Step 5

Convert Improper Fraction to a Mixed Number

Since the numerator (287) is greater than the denominator (208), divide 287 by 208: it goes in 1 whole time(s) with a remainder of 79, giving the mixed number 1 79/208.

287/208 = 179/208

Step 6

Decimal & Percentage Representation

Dividing the numerator 287 by denominator 208 produces a repeating decimal (approximately 1.379808, or 137.9808%).

287 ÷ 208 = 1.379808 (137.9808%)

Visual Representation

The diagram below illustrates 11/16 plus 9/13 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`287/208`
Mixed Number Form	`1 79/208`
Decimal Form	`1.379808`
Percentage	`137.9808%`

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Frequently Asked Questions

What is 11/16 plus 9/13 as a fraction?

11/16 + 9/13 in simplest fraction form is 287/208 (or 1 79/208 as a mixed number).

What is 11/16 plus 9/13 as a decimal?

11/16 + 9/13 converted to a decimal is 1.379808.

What is 11/16 plus 9/13 as a percentage?

11/16 + 9/13 expressed as a percentage is 137.9808%.

How do you write 11/16 plus 9/13 as a mixed number?

Because the numerator is greater than the denominator, the improper fraction 287/208 can be written as the mixed number 1 79/208.

Does 11/16 plus 9/13 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 1.379808...) because the denominator contains prime factors other than 2 and 5.