What is 8/33 plus 7/21? (Answer: 19/33)

Exact Answer

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Problem: What is 8/33 plus 7/21?
Formula / Expression: 8/33 + 7/21
Final Answer: 19/33
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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 8/33 by 7, and multiply the numerator and denominator of 7/21 by 11 so both fractions share the common base 231.
Working: 8 × 7/33 × 7 = 56/231 and 7 × 11/21 × 11 = 77/231

Step 3: Add the Numerators
Now add the numerators (56 + 77 = 133) and keep the common denominator 231 unchanged.
Working: 56 + 77/231 = 133/231

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 133 and 231, which is 7. Divide both the numerator and denominator by 7.
Working: 133 ÷ 7/231 ÷ 7 = 19/33

Step 5: Decimal & Percentage Representation
Dividing the numerator 19 by denominator 33 produces a repeating decimal (approximately 0.575758, or 57.5758%).
Working: 19 ÷ 33 = 0.575758 (57.5758%)

Key Values:
- Simplified Fraction: 19/33
- Mixed Number Form: 19/33
- Decimal Value: 0.575758
- Percentage: 57.5758%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-8-33-plus-7-21/
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8/33 + 7/21 = 19/33

Simplified Fraction

19/33

Mixed Number

Proper (19/33)

Decimal Value

0.575758

Percentage

57.5758%

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Step-by-Step Solution: 8/33 + 7/21

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 8/33 by 7, and multiply the numerator and denominator of 7/21 by 11 so both fractions share the common base 231.

8 × 7/33 × 7 = 56/231 and 7 × 11/21 × 11 = 77/231

Step 3

Add the Numerators

Now add the numerators (56 + 77 = 133) and keep the common denominator 231 unchanged.

56 + 77/231 = 133/231

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 133 and 231, which is 7. Divide both the numerator and denominator by 7.

133 ÷ 7/231 ÷ 7 = 19/33

Step 5

Decimal & Percentage Representation

Dividing the numerator 19 by denominator 33 produces a repeating decimal (approximately 0.575758, or 57.5758%).

19 ÷ 33 = 0.575758 (57.5758%)

Visual Representation

The diagram below illustrates 8/33 plus 7/21 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`19/33`
Mixed Number Form	`19/33`
Decimal Form	`0.575758`
Percentage	`57.5758%`

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Frequently Asked Questions

What is 8/33 plus 7/21 as a fraction?

8/33 + 7/21 in simplest fraction form is 19/33.

What is 8/33 plus 7/21 as a decimal?

8/33 + 7/21 converted to a decimal is 0.575758.

What is 8/33 plus 7/21 as a percentage?

8/33 + 7/21 expressed as a percentage is 57.5758%.

Does 8/33 plus 7/21 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.575758...) because the denominator contains prime factors other than 2 and 5.