What is 5/21 plus 12/49? (Answer: 71/147)

Exact Answer

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Problem: What is 5/21 plus 12/49?
Formula / Expression: 5/21 + 12/49
Final Answer: 71/147
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 21 and 49 share a common factor (GCD = 7). Finding their Least Common Multiple gives an LCD of 147 (which is smaller than their product 21 × 49 = 1029, keeping the calculation simpler).
Working: LCD(21, 49) = 147

Step 2: Convert to Equivalent Fractions with Common Denominator 147
Multiply the numerator and denominator of 5/21 by 7, and multiply the numerator and denominator of 12/49 by 3 so both fractions share the common base 147.
Working: 5 × 7/21 × 7 = 35/147 and 12 × 3/49 × 3 = 36/147

Step 3: Add the Numerators
Now add the numerators (35 + 36 = 71) and keep the common denominator 147 unchanged.
Working: 35 + 36/147 = 71/147

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 71 and 147 is 1, confirming that 71/147 cannot be reduced further—it is already in its simplest irreducible form.
Working: 71/147

Step 5: Decimal & Percentage Representation
Dividing the numerator 71 by denominator 147 produces a repeating decimal (approximately 0.482993, or 48.2993%).
Working: 71 ÷ 147 = 0.482993 (48.2993%)

Key Values:
- Simplified Fraction: 71/147
- Mixed Number Form: 71/147
- Decimal Value: 0.482993
- Percentage: 48.2993%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-5-21-plus-12-49/
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5/21 + 12/49 = 71/147

Simplified Fraction

71/147

Mixed Number

Proper (71/147)

Decimal Value

0.482993

Percentage

48.2993%

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Step-by-Step Solution: 5/21 + 12/49

Step 1

Find the Least Common Denominator (LCD)

The denominators 21 and 49 share a common factor (GCD = 7). Finding their Least Common Multiple gives an LCD of 147 (which is smaller than their product 21 × 49 = 1029, keeping the calculation simpler).

LCD(21, 49) = 147

Step 2

Convert to Equivalent Fractions with Common Denominator 147

Multiply the numerator and denominator of 5/21 by 7, and multiply the numerator and denominator of 12/49 by 3 so both fractions share the common base 147.

5 × 7/21 × 7 = 35/147 and 12 × 3/49 × 3 = 36/147

Step 3

Add the Numerators

Now add the numerators (35 + 36 = 71) and keep the common denominator 147 unchanged.

35 + 36/147 = 71/147

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 71 and 147 is 1, confirming that 71/147 cannot be reduced further—it is already in its simplest irreducible form.

71/147

Step 5

Decimal & Percentage Representation

Dividing the numerator 71 by denominator 147 produces a repeating decimal (approximately 0.482993, or 48.2993%).

71 ÷ 147 = 0.482993 (48.2993%)

Visual Representation

The diagram below illustrates 5/21 plus 12/49 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`71/147`
Mixed Number Form	`71/147`
Decimal Form	`0.482993`
Percentage	`48.2993%`

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Frequently Asked Questions

What is 5/21 plus 12/49 as a fraction?

5/21 + 12/49 in simplest fraction form is 71/147.

What is 5/21 plus 12/49 as a decimal?

5/21 + 12/49 converted to a decimal is 0.482993.

What is 5/21 plus 12/49 as a percentage?

5/21 + 12/49 expressed as a percentage is 48.2993%.

Does 5/21 plus 12/49 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.482993...) because the denominator contains prime factors other than 2 and 5.