What is 20/56 plus 8/21? (Answer: 31/42)

Exact Answer

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Problem: What is 20/56 plus 8/21?
Formula / Expression: 20/56 + 8/21
Final Answer: 31/42
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 56 and 21 share a common factor (GCD = 7). Finding their Least Common Multiple gives an LCD of 168 (which is smaller than their product 56 × 21 = 1176, keeping the calculation simpler).
Working: LCD(56, 21) = 168

Step 2: Convert to Equivalent Fractions with Common Denominator 168
Multiply the numerator and denominator of 20/56 by 3, and multiply the numerator and denominator of 8/21 by 8 so both fractions share the common base 168.
Working: 20 × 3/56 × 3 = 60/168 and 8 × 8/21 × 8 = 64/168

Step 3: Add the Numerators
Now add the numerators (60 + 64 = 124) and keep the common denominator 168 unchanged.
Working: 60 + 64/168 = 124/168

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 124 and 168, which is 4. Divide both the numerator and denominator by 4.
Working: 124 ÷ 4/168 ÷ 4 = 31/42

Step 5: Decimal & Percentage Representation
Dividing the numerator 31 by denominator 42 produces a repeating decimal (approximately 0.738095, or 73.8095%).
Working: 31 ÷ 42 = 0.738095 (73.8095%)

Key Values:
- Simplified Fraction: 31/42
- Mixed Number Form: 31/42
- Decimal Value: 0.738095
- Percentage: 73.8095%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-20-56-plus-8-21/
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20/56 + 8/21 = 31/42

Simplified Fraction

31/42

Mixed Number

Proper (31/42)

Decimal Value

0.738095

Percentage

73.8095%

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Step-by-Step Solution: 20/56 + 8/21

Step 1

Find the Least Common Denominator (LCD)

The denominators 56 and 21 share a common factor (GCD = 7). Finding their Least Common Multiple gives an LCD of 168 (which is smaller than their product 56 × 21 = 1176, keeping the calculation simpler).

LCD(56, 21) = 168

Step 2

Convert to Equivalent Fractions with Common Denominator 168

Multiply the numerator and denominator of 20/56 by 3, and multiply the numerator and denominator of 8/21 by 8 so both fractions share the common base 168.

20 × 3/56 × 3 = 60/168 and 8 × 8/21 × 8 = 64/168

Step 3

Add the Numerators

Now add the numerators (60 + 64 = 124) and keep the common denominator 168 unchanged.

60 + 64/168 = 124/168

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 124 and 168, which is 4. Divide both the numerator and denominator by 4.

124 ÷ 4/168 ÷ 4 = 31/42

Step 5

Decimal & Percentage Representation

Dividing the numerator 31 by denominator 42 produces a repeating decimal (approximately 0.738095, or 73.8095%).

31 ÷ 42 = 0.738095 (73.8095%)

Visual Representation

The diagram below illustrates 20/56 plus 8/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`31/42`
Mixed Number Form	`31/42`
Decimal Form	`0.738095`
Percentage	`73.8095%`

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Frequently Asked Questions

What is 20/56 plus 8/21 as a fraction?

20/56 + 8/21 in simplest fraction form is 31/42.

What is 20/56 plus 8/21 as a decimal?

20/56 + 8/21 converted to a decimal is 0.738095.

What is 20/56 plus 8/21 as a percentage?

20/56 + 8/21 expressed as a percentage is 73.8095%.

Does 20/56 plus 8/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.738095...) because the denominator contains prime factors other than 2 and 5.