What is 11/29 plus 9/21? (Answer: 164/203)

Exact Answer

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Problem: What is 11/29 plus 9/21?
Formula / Expression: 11/29 + 9/21
Final Answer: 164/203
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 29 and 21 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 29 × 21 = 609.
Working: LCD(29, 21) = 609

Step 2: Convert to Equivalent Fractions with Common Denominator 609
Multiply the numerator and denominator of 11/29 by 21, and multiply the numerator and denominator of 9/21 by 29 so both fractions share the common base 609.
Working: 11 × 21/29 × 21 = 231/609 and 9 × 29/21 × 29 = 261/609

Step 3: Add the Numerators
Now add the numerators (231 + 261 = 492) and keep the common denominator 609 unchanged.
Working: 231 + 261/609 = 492/609

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 492 and 609, which is 3. Divide both the numerator and denominator by 3.
Working: 492 ÷ 3/609 ÷ 3 = 164/203

Step 5: Decimal & Percentage Representation
Dividing the numerator 164 by denominator 203 produces a repeating decimal (approximately 0.807882, or 80.7882%).
Working: 164 ÷ 203 = 0.807882 (80.7882%)

Key Values:
- Simplified Fraction: 164/203
- Mixed Number Form: 164/203
- Decimal Value: 0.807882
- Percentage: 80.7882%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-11-29-plus-9-21/
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11/29 + 9/21 = 164/203

Simplified Fraction

164/203

Mixed Number

Proper (164/203)

Decimal Value

0.807882

Percentage

80.7882%

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Step-by-Step Solution: 11/29 + 9/21

Step 1

Find the Least Common Denominator (LCD)

The denominators 29 and 21 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 29 × 21 = 609.

LCD(29, 21) = 609

Step 2

Convert to Equivalent Fractions with Common Denominator 609

Multiply the numerator and denominator of 11/29 by 21, and multiply the numerator and denominator of 9/21 by 29 so both fractions share the common base 609.

11 × 21/29 × 21 = 231/609 and 9 × 29/21 × 29 = 261/609

Step 3

Add the Numerators

Now add the numerators (231 + 261 = 492) and keep the common denominator 609 unchanged.

231 + 261/609 = 492/609

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 492 and 609, which is 3. Divide both the numerator and denominator by 3.

492 ÷ 3/609 ÷ 3 = 164/203

Step 5

Decimal & Percentage Representation

Dividing the numerator 164 by denominator 203 produces a repeating decimal (approximately 0.807882, or 80.7882%).

164 ÷ 203 = 0.807882 (80.7882%)

Visual Representation

The diagram below illustrates 11/29 plus 9/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`164/203`
Mixed Number Form	`164/203`
Decimal Form	`0.807882`
Percentage	`80.7882%`

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Frequently Asked Questions

What is 11/29 plus 9/21 as a fraction?

11/29 + 9/21 in simplest fraction form is 164/203.

What is 11/29 plus 9/21 as a decimal?

11/29 + 9/21 converted to a decimal is 0.807882.

What is 11/29 plus 9/21 as a percentage?

11/29 + 9/21 expressed as a percentage is 80.7882%.

Does 11/29 plus 9/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.807882...) because the denominator contains prime factors other than 2 and 5.