What is 5/33 plus 15/21? (Answer: 200/231)

Exact Answer

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Problem: What is 5/33 plus 15/21?
Formula / Expression: 5/33 + 15/21
Final Answer: 200/231
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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 5/33 by 7, and multiply the numerator and denominator of 15/21 by 11 so both fractions share the common base 231.
Working: 5 × 7/33 × 7 = 35/231 and 15 × 11/21 × 11 = 165/231

Step 3: Add the Numerators
Now add the numerators (35 + 165 = 200) and keep the common denominator 231 unchanged.
Working: 35 + 165/231 = 200/231

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 200 and 231 is 1, confirming that 200/231 cannot be reduced further—it is already in its simplest irreducible form.
Working: 200/231

Step 5: Decimal & Percentage Representation
Dividing the numerator 200 by denominator 231 produces a repeating decimal (approximately 0.865801, or 86.5801%).
Working: 200 ÷ 231 = 0.865801 (86.5801%)

Key Values:
- Simplified Fraction: 200/231
- Mixed Number Form: 200/231
- Decimal Value: 0.865801
- Percentage: 86.5801%

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5/33 + 15/21 = 200/231

Simplified Fraction

200/231

Mixed Number

Proper (200/231)

Decimal Value

0.865801

Percentage

86.5801%

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Step-by-Step Solution: 5/33 + 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 5/33 by 7, and multiply the numerator and denominator of 15/21 by 11 so both fractions share the common base 231.

5 × 7/33 × 7 = 35/231 and 15 × 11/21 × 11 = 165/231

Step 3

Add the Numerators

Now add the numerators (35 + 165 = 200) and keep the common denominator 231 unchanged.

35 + 165/231 = 200/231

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 200 and 231 is 1, confirming that 200/231 cannot be reduced further—it is already in its simplest irreducible form.

200/231

Step 5

Decimal & Percentage Representation

Dividing the numerator 200 by denominator 231 produces a repeating decimal (approximately 0.865801, or 86.5801%).

200 ÷ 231 = 0.865801 (86.5801%)

Visual Representation

The diagram below illustrates 5/33 plus 15/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`200/231`
Mixed Number Form	`200/231`
Decimal Form	`0.865801`
Percentage	`86.5801%`

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Frequently Asked Questions

What is 5/33 plus 15/21 as a fraction?

5/33 + 15/21 in simplest fraction form is 200/231.

What is 5/33 plus 15/21 as a decimal?

5/33 + 15/21 converted to a decimal is 0.865801.

What is 5/33 plus 15/21 as a percentage?

5/33 + 15/21 expressed as a percentage is 86.5801%.

Does 5/33 plus 15/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.865801...) because the denominator contains prime factors other than 2 and 5.