What is 11/24 plus 11/21? (Answer: 55/56)

Exact Answer

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Problem: What is 11/24 plus 11/21?
Formula / Expression: 11/24 + 11/21
Final Answer: 55/56
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 24 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 168 (which is smaller than their product 24 × 21 = 504, keeping the calculation simpler).
Working: LCD(24, 21) = 168

Step 2: Convert to Equivalent Fractions with Common Denominator 168
Multiply the numerator and denominator of 11/24 by 7, and multiply the numerator and denominator of 11/21 by 8 so both fractions share the common base 168.
Working: 11 × 7/24 × 7 = 77/168 and 11 × 8/21 × 8 = 88/168

Step 3: Add the Numerators
Now add the numerators (77 + 88 = 165) and keep the common denominator 168 unchanged.
Working: 77 + 88/168 = 165/168

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 165 and 168, which is 3. Divide both the numerator and denominator by 3.
Working: 165 ÷ 3/168 ÷ 3 = 55/56

Step 5: Decimal & Percentage Representation
Dividing the numerator 55 by denominator 56 produces a repeating decimal (approximately 0.982143, or 98.2143%).
Working: 55 ÷ 56 = 0.982143 (98.2143%)

Key Values:
- Simplified Fraction: 55/56
- Mixed Number Form: 55/56
- Decimal Value: 0.982143
- Percentage: 98.2143%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-11-24-plus-11-21/
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11/24 + 11/21 = 55/56

Simplified Fraction

55/56

Mixed Number

Proper (55/56)

Decimal Value

0.982143

Percentage

98.2143%

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Step-by-Step Solution: 11/24 + 11/21

Step 1

Find the Least Common Denominator (LCD)

The denominators 24 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 168 (which is smaller than their product 24 × 21 = 504, keeping the calculation simpler).

LCD(24, 21) = 168

Step 2

Convert to Equivalent Fractions with Common Denominator 168

Multiply the numerator and denominator of 11/24 by 7, and multiply the numerator and denominator of 11/21 by 8 so both fractions share the common base 168.

11 × 7/24 × 7 = 77/168 and 11 × 8/21 × 8 = 88/168

Step 3

Add the Numerators

Now add the numerators (77 + 88 = 165) and keep the common denominator 168 unchanged.

77 + 88/168 = 165/168

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 165 and 168, which is 3. Divide both the numerator and denominator by 3.

165 ÷ 3/168 ÷ 3 = 55/56

Step 5

Decimal & Percentage Representation

Dividing the numerator 55 by denominator 56 produces a repeating decimal (approximately 0.982143, or 98.2143%).

55 ÷ 56 = 0.982143 (98.2143%)

Visual Representation

The diagram below illustrates 11/24 plus 11/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`55/56`
Mixed Number Form	`55/56`
Decimal Form	`0.982143`
Percentage	`98.2143%`

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Frequently Asked Questions

What is 11/24 plus 11/21 as a fraction?

11/24 + 11/21 in simplest fraction form is 55/56.

What is 11/24 plus 11/21 as a decimal?

11/24 + 11/21 converted to a decimal is 0.982143.

What is 11/24 plus 11/21 as a percentage?

11/24 + 11/21 expressed as a percentage is 98.2143%.

Does 11/24 plus 11/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.982143...) because the denominator contains prime factors other than 2 and 5.