What is 8/49 plus 15/21? (Answer: 43/49)

Exact Answer

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Problem: What is 8/49 plus 15/21?
Formula / Expression: 8/49 + 15/21
Final Answer: 43/49
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Step-by-Step Solution:

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

Step 2: Convert to Equivalent Fractions with Common Denominator 147
Multiply the numerator and denominator of 8/49 by 3, and multiply the numerator and denominator of 15/21 by 7 so both fractions share the common base 147.
Working: 8 × 3/49 × 3 = 24/147 and 15 × 7/21 × 7 = 105/147

Step 3: Add the Numerators
Now add the numerators (24 + 105 = 129) and keep the common denominator 147 unchanged.
Working: 24 + 105/147 = 129/147

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 129 and 147, which is 3. Divide both the numerator and denominator by 3.
Working: 129 ÷ 3/147 ÷ 3 = 43/49

Step 5: Decimal & Percentage Representation
Dividing the numerator 43 by denominator 49 produces a repeating decimal (approximately 0.877551, or 87.7551%).
Working: 43 ÷ 49 = 0.877551 (87.7551%)

Key Values:
- Simplified Fraction: 43/49
- Mixed Number Form: 43/49
- Decimal Value: 0.877551
- Percentage: 87.7551%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-8-49-plus-15-21/
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8/49 + 15/21 = 43/49

Simplified Fraction

43/49

Mixed Number

Proper (43/49)

Decimal Value

0.877551

Percentage

87.7551%

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Step-by-Step Solution: 8/49 + 15/21

Step 1

Find the Least Common Denominator (LCD)

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

LCD(49, 21) = 147

Step 2

Convert to Equivalent Fractions with Common Denominator 147

Multiply the numerator and denominator of 8/49 by 3, and multiply the numerator and denominator of 15/21 by 7 so both fractions share the common base 147.

8 × 3/49 × 3 = 24/147 and 15 × 7/21 × 7 = 105/147

Step 3

Add the Numerators

Now add the numerators (24 + 105 = 129) and keep the common denominator 147 unchanged.

24 + 105/147 = 129/147

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 129 and 147, which is 3. Divide both the numerator and denominator by 3.

129 ÷ 3/147 ÷ 3 = 43/49

Step 5

Decimal & Percentage Representation

Dividing the numerator 43 by denominator 49 produces a repeating decimal (approximately 0.877551, or 87.7551%).

43 ÷ 49 = 0.877551 (87.7551%)

Visual Representation

The diagram below illustrates 8/49 plus 15/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`43/49`
Mixed Number Form	`43/49`
Decimal Form	`0.877551`
Percentage	`87.7551%`

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Frequently Asked Questions

What is 8/49 plus 15/21 as a fraction?

8/49 + 15/21 in simplest fraction form is 43/49.

What is 8/49 plus 15/21 as a decimal?

8/49 + 15/21 converted to a decimal is 0.877551.

What is 8/49 plus 15/21 as a percentage?

8/49 + 15/21 expressed as a percentage is 87.7551%.

Does 8/49 plus 15/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.877551...) because the denominator contains prime factors other than 2 and 5.