What is 4/18 plus 3/9? (Answer: 5/9)

Exact Answer

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Problem: What is 4/18 plus 3/9?
Formula / Expression: 4/18 + 3/9
Final Answer: 5/9
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
Notice that 18 is an exact multiple of 9 (9 × 2 = 18). The Least Common Denominator (LCD) is simply 18, meaning we only need to scale one fraction.
Working: LCD(18, 9) = 18

Step 2: Convert to Equivalent Fractions with Common Denominator 18
Multiply the numerator and denominator of 4/18 by 1, and multiply the numerator and denominator of 3/9 by 2 so both fractions share the common base 18.
Working: 4 × 1/18 × 1 = 4/18 and 3 × 2/9 × 2 = 6/18

Step 3: Add the Numerators
Now add the numerators (4 + 6 = 10) and keep the common denominator 18 unchanged.
Working: 4 + 6/18 = 10/18

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 10 and 18, which is 2. Divide both the numerator and denominator by 2.
Working: 10 ÷ 2/18 ÷ 2 = 5/9

Step 5: Decimal & Percentage Representation
Dividing the numerator 5 by denominator 9 produces a repeating decimal (approximately 0.555556, or 55.5556%).
Working: 5 ÷ 9 = 0.555556 (55.5556%)

Key Values:
- Simplified Fraction: 5/9
- Mixed Number Form: 5/9
- Decimal Value: 0.555556
- Percentage: 55.5556%

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Solved with FractionsCalc:
https://fractionscalc.com/what-is-4-18-plus-3-9/
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4/18 + 3/9 = 5/9

Simplified Fraction

5/9

Mixed Number

Proper (5/9)

Decimal Value

0.555556

Percentage

55.5556%

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Step-by-Step Solution: 4/18 + 3/9

Step 1

Find the Least Common Denominator (LCD)

Notice that 18 is an exact multiple of 9 (9 × 2 = 18). The Least Common Denominator (LCD) is simply 18, meaning we only need to scale one fraction.

LCD(18, 9) = 18

Step 2

Convert to Equivalent Fractions with Common Denominator 18

Multiply the numerator and denominator of 4/18 by 1, and multiply the numerator and denominator of 3/9 by 2 so both fractions share the common base 18.

4 × 1/18 × 1 = 4/18 and 3 × 2/9 × 2 = 6/18

Step 3

Add the Numerators

Now add the numerators (4 + 6 = 10) and keep the common denominator 18 unchanged.

4 + 6/18 = 10/18

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 10 and 18, which is 2. Divide both the numerator and denominator by 2.

10 ÷ 2/18 ÷ 2 = 5/9

Step 5

Decimal & Percentage Representation

Dividing the numerator 5 by denominator 9 produces a repeating decimal (approximately 0.555556, or 55.5556%).

5 ÷ 9 = 0.555556 (55.5556%)

Visual Representation

The diagram below illustrates 4/18 plus 3/9 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`5/9`
Mixed Number Form	`5/9`
Decimal Form	`0.555556`
Percentage	`55.5556%`

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Frequently Asked Questions

What is 4/18 plus 3/9 as a fraction?

4/18 + 3/9 in simplest fraction form is 5/9.

What is 4/18 plus 3/9 as a decimal?

4/18 + 3/9 converted to a decimal is 0.555556.

What is 4/18 plus 3/9 as a percentage?

4/18 + 3/9 expressed as a percentage is 55.5556%.

Does 4/18 plus 3/9 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.555556...) because the denominator contains prime factors other than 2 and 5.