What is 13/48 plus 15/21? (Answer: 331/336)

Exact Answer

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Problem: What is 13/48 plus 15/21?
Formula / Expression: 13/48 + 15/21
Final Answer: 331/336
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 48 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 336 (which is smaller than their product 48 × 21 = 1008, keeping the calculation simpler).
Working: LCD(48, 21) = 336

Step 2: Convert to Equivalent Fractions with Common Denominator 336
Multiply the numerator and denominator of 13/48 by 7, and multiply the numerator and denominator of 15/21 by 16 so both fractions share the common base 336.
Working: 13 × 7/48 × 7 = 91/336 and 15 × 16/21 × 16 = 240/336

Step 3: Add the Numerators
Now add the numerators (91 + 240 = 331) and keep the common denominator 336 unchanged.
Working: 91 + 240/336 = 331/336

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 331 and 336 is 1, confirming that 331/336 cannot be reduced further—it is already in its simplest irreducible form.
Working: 331/336

Step 5: Decimal & Percentage Representation
Dividing the numerator 331 by denominator 336 produces a repeating decimal (approximately 0.985119, or 98.5119%).
Working: 331 ÷ 336 = 0.985119 (98.5119%)

Key Values:
- Simplified Fraction: 331/336
- Mixed Number Form: 331/336
- Decimal Value: 0.985119
- Percentage: 98.5119%

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Solved with FractionsCalc:
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13/48 + 15/21 = 331/336

Simplified Fraction

331/336

Mixed Number

Proper (331/336)

Decimal Value

0.985119

Percentage

98.5119%

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Step-by-Step Solution: 13/48 + 15/21

Step 1

Find the Least Common Denominator (LCD)

The denominators 48 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 336 (which is smaller than their product 48 × 21 = 1008, keeping the calculation simpler).

LCD(48, 21) = 336

Step 2

Convert to Equivalent Fractions with Common Denominator 336

Multiply the numerator and denominator of 13/48 by 7, and multiply the numerator and denominator of 15/21 by 16 so both fractions share the common base 336.

13 × 7/48 × 7 = 91/336 and 15 × 16/21 × 16 = 240/336

Step 3

Add the Numerators

Now add the numerators (91 + 240 = 331) and keep the common denominator 336 unchanged.

91 + 240/336 = 331/336

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 331 and 336 is 1, confirming that 331/336 cannot be reduced further—it is already in its simplest irreducible form.

331/336

Step 5

Decimal & Percentage Representation

Dividing the numerator 331 by denominator 336 produces a repeating decimal (approximately 0.985119, or 98.5119%).

331 ÷ 336 = 0.985119 (98.5119%)

Visual Representation

The diagram below illustrates 13/48 plus 15/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`331/336`
Mixed Number Form	`331/336`
Decimal Form	`0.985119`
Percentage	`98.5119%`

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Frequently Asked Questions

What is 13/48 plus 15/21 as a fraction?

13/48 + 15/21 in simplest fraction form is 331/336.

What is 13/48 plus 15/21 as a decimal?

13/48 + 15/21 converted to a decimal is 0.985119.

What is 13/48 plus 15/21 as a percentage?

13/48 + 15/21 expressed as a percentage is 98.5119%.

Does 13/48 plus 15/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.985119...) because the denominator contains prime factors other than 2 and 5.