What is 6/33 plus 15/21? (Answer: 69/77)

Exact Answer

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Problem: What is 6/33 plus 15/21?
Formula / Expression: 6/33 + 15/21
Final Answer: 69/77
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 33 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 231 (which is smaller than their product 33 × 21 = 693, keeping the calculation simpler).
Working: LCD(33, 21) = 231

Step 2: Convert to Equivalent Fractions with Common Denominator 231
Multiply the numerator and denominator of 6/33 by 7, and multiply the numerator and denominator of 15/21 by 11 so both fractions share the common base 231.
Working: 6 × 7/33 × 7 = 42/231 and 15 × 11/21 × 11 = 165/231

Step 3: Add the Numerators
Now add the numerators (42 + 165 = 207) and keep the common denominator 231 unchanged.
Working: 42 + 165/231 = 207/231

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 207 and 231, which is 3. Divide both the numerator and denominator by 3.
Working: 207 ÷ 3/231 ÷ 3 = 69/77

Step 5: Decimal & Percentage Representation
Dividing the numerator 69 by denominator 77 produces a repeating decimal (approximately 0.896104, or 89.6104%).
Working: 69 ÷ 77 = 0.896104 (89.6104%)

Key Values:
- Simplified Fraction: 69/77
- Mixed Number Form: 69/77
- Decimal Value: 0.896104
- Percentage: 89.6104%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-6-33-plus-15-21/
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6/33 + 15/21 = 69/77

Simplified Fraction

69/77

Mixed Number

Proper (69/77)

Decimal Value

0.896104

Percentage

89.6104%

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Step-by-Step Solution: 6/33 + 15/21

Step 1

Find the Least Common Denominator (LCD)

The denominators 33 and 21 share a common factor (GCD = 3). Finding their Least Common Multiple gives an LCD of 231 (which is smaller than their product 33 × 21 = 693, keeping the calculation simpler).

LCD(33, 21) = 231

Step 2

Convert to Equivalent Fractions with Common Denominator 231

Multiply the numerator and denominator of 6/33 by 7, and multiply the numerator and denominator of 15/21 by 11 so both fractions share the common base 231.

6 × 7/33 × 7 = 42/231 and 15 × 11/21 × 11 = 165/231

Step 3

Add the Numerators

Now add the numerators (42 + 165 = 207) and keep the common denominator 231 unchanged.

42 + 165/231 = 207/231

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 207 and 231, which is 3. Divide both the numerator and denominator by 3.

207 ÷ 3/231 ÷ 3 = 69/77

Step 5

Decimal & Percentage Representation

Dividing the numerator 69 by denominator 77 produces a repeating decimal (approximately 0.896104, or 89.6104%).

69 ÷ 77 = 0.896104 (89.6104%)

Visual Representation

The diagram below illustrates 6/33 plus 15/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`69/77`
Mixed Number Form	`69/77`
Decimal Form	`0.896104`
Percentage	`89.6104%`

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Frequently Asked Questions

What is 6/33 plus 15/21 as a fraction?

6/33 + 15/21 in simplest fraction form is 69/77.

What is 6/33 plus 15/21 as a decimal?

6/33 + 15/21 converted to a decimal is 0.896104.

What is 6/33 plus 15/21 as a percentage?

6/33 + 15/21 expressed as a percentage is 89.6104%.

Does 6/33 plus 15/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.896104...) because the denominator contains prime factors other than 2 and 5.