What is 12/36 plus 11/21? (Answer: 6/7)

Exact Answer

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Problem: What is 12/36 plus 11/21?
Formula / Expression: 12/36 + 11/21
Final Answer: 6/7
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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 12/36 by 7, and multiply the numerator and denominator of 11/21 by 12 so both fractions share the common base 252.
Working: 12 × 7/36 × 7 = 84/252 and 11 × 12/21 × 12 = 132/252

Step 3: Add the Numerators
Now add the numerators (84 + 132 = 216) and keep the common denominator 252 unchanged.
Working: 84 + 132/252 = 216/252

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 216 and 252, which is 36. Divide both the numerator and denominator by 36.
Working: 216 ÷ 36/252 ÷ 36 = 6/7

Step 5: Decimal & Percentage Representation
Dividing the numerator 6 by denominator 7 produces a repeating decimal (approximately 0.857143, or 85.7143%).
Working: 6 ÷ 7 = 0.857143 (85.7143%)

Key Values:
- Simplified Fraction: 6/7
- Mixed Number Form: 6/7
- Decimal Value: 0.857143
- Percentage: 85.7143%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-12-36-plus-11-21/
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12/36 + 11/21 = 6/7

Simplified Fraction

6/7

Mixed Number

Proper (6/7)

Decimal Value

0.857143

Percentage

85.7143%

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Step-by-Step Solution: 12/36 + 11/21

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 12/36 by 7, and multiply the numerator and denominator of 11/21 by 12 so both fractions share the common base 252.

12 × 7/36 × 7 = 84/252 and 11 × 12/21 × 12 = 132/252

Step 3

Add the Numerators

Now add the numerators (84 + 132 = 216) and keep the common denominator 252 unchanged.

84 + 132/252 = 216/252

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 216 and 252, which is 36. Divide both the numerator and denominator by 36.

216 ÷ 36/252 ÷ 36 = 6/7

Step 5

Decimal & Percentage Representation

Dividing the numerator 6 by denominator 7 produces a repeating decimal (approximately 0.857143, or 85.7143%).

6 ÷ 7 = 0.857143 (85.7143%)

Visual Representation

The diagram below illustrates 12/36 plus 11/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`6/7`
Mixed Number Form	`6/7`
Decimal Form	`0.857143`
Percentage	`85.7143%`

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Frequently Asked Questions

What is 12/36 plus 11/21 as a fraction?

12/36 + 11/21 in simplest fraction form is 6/7.

What is 12/36 plus 11/21 as a decimal?

12/36 + 11/21 converted to a decimal is 0.857143.

What is 12/36 plus 11/21 as a percentage?

12/36 + 11/21 expressed as a percentage is 85.7143%.

Does 12/36 plus 11/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.857143...) because the denominator contains prime factors other than 2 and 5.