What is 7/36 plus 15/21? (Answer: 229/252)

Exact Answer

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Problem: What is 7/36 plus 15/21?
Formula / Expression: 7/36 + 15/21
Final Answer: 229/252
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 36 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 252 (which is smaller than their product 36 × 21 = 756, keeping the calculation simpler).
Working: LCD(36, 21) = 252

Step 2: Convert to Equivalent Fractions with Common Denominator 252
Multiply the numerator and denominator of 7/36 by 7, and multiply the numerator and denominator of 15/21 by 12 so both fractions share the common base 252.
Working: 7 × 7/36 × 7 = 49/252 and 15 × 12/21 × 12 = 180/252

Step 3: Add the Numerators
Now add the numerators (49 + 180 = 229) and keep the common denominator 252 unchanged.
Working: 49 + 180/252 = 229/252

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 229 and 252 is 1, confirming that 229/252 cannot be reduced further—it is already in its simplest irreducible form.
Working: 229/252

Step 5: Decimal & Percentage Representation
Dividing the numerator 229 by denominator 252 produces a repeating decimal (approximately 0.90873, or 90.873%).
Working: 229 ÷ 252 = 0.90873 (90.873%)

Key Values:
- Simplified Fraction: 229/252
- Mixed Number Form: 229/252
- Decimal Value: 0.90873
- Percentage: 90.873%

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Solved with FractionsCalc:
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7/36 + 15/21 = 229/252

Simplified Fraction

229/252

Mixed Number

Proper (229/252)

Decimal Value

0.90873

Percentage

90.873%

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Step-by-Step Solution: 7/36 + 15/21

Step 1

Find the Least Common Denominator (LCD)

The denominators 36 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 252 (which is smaller than their product 36 × 21 = 756, keeping the calculation simpler).

LCD(36, 21) = 252

Step 2

Convert to Equivalent Fractions with Common Denominator 252

Multiply the numerator and denominator of 7/36 by 7, and multiply the numerator and denominator of 15/21 by 12 so both fractions share the common base 252.

7 × 7/36 × 7 = 49/252 and 15 × 12/21 × 12 = 180/252

Step 3

Add the Numerators

Now add the numerators (49 + 180 = 229) and keep the common denominator 252 unchanged.

49 + 180/252 = 229/252

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 229 and 252 is 1, confirming that 229/252 cannot be reduced further—it is already in its simplest irreducible form.

229/252

Step 5

Decimal & Percentage Representation

Dividing the numerator 229 by denominator 252 produces a repeating decimal (approximately 0.90873, or 90.873%).

229 ÷ 252 = 0.90873 (90.873%)

Visual Representation

The diagram below illustrates 7/36 plus 15/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`229/252`
Mixed Number Form	`229/252`
Decimal Form	`0.90873`
Percentage	`90.873%`

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Frequently Asked Questions

What is 7/36 plus 15/21 as a fraction?

7/36 + 15/21 in simplest fraction form is 229/252.

What is 7/36 plus 15/21 as a decimal?

7/36 + 15/21 converted to a decimal is 0.90873.

What is 7/36 plus 15/21 as a percentage?

7/36 + 15/21 expressed as a percentage is 90.873%.

Does 7/36 plus 15/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.90873...) because the denominator contains prime factors other than 2 and 5.