What is 1/9 plus 2/5? (Answer: 23/45)

Exact Answer

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Problem: What is 1/9 plus 2/5?
Formula / Expression: 1/9 + 2/5
Final Answer: 23/45
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 9 and 5 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 9 × 5 = 45.
Working: LCD(9, 5) = 45

Step 2: Convert to Equivalent Fractions with Common Denominator 45
Multiply the numerator and denominator of 1/9 by 5, and multiply the numerator and denominator of 2/5 by 9 so both fractions share the common base 45.
Working: 1 × 5/9 × 5 = 5/45 and 2 × 9/5 × 9 = 18/45

Step 3: Add the Numerators
Now add the numerators (5 + 18 = 23) and keep the common denominator 45 unchanged.
Working: 5 + 18/45 = 23/45

Step 4: Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 23 and 45 is 1, confirming that 23/45 cannot be reduced further—it is already in its simplest irreducible form.
Working: 23/45

Step 5: Decimal & Percentage Representation
Dividing the numerator 23 by denominator 45 produces a repeating decimal (approximately 0.511111, or 51.1111%).
Working: 23 ÷ 45 = 0.511111 (51.1111%)

Key Values:
- Simplified Fraction: 23/45
- Mixed Number Form: 23/45
- Decimal Value: 0.511111
- Percentage: 51.1111%

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Solved with FractionsCalc:
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1/9 + 2/5 = 23/45

Simplified Fraction

23/45

Mixed Number

Proper (23/45)

Decimal Value

0.511111

Percentage

51.1111%

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Step-by-Step Solution: 1/9 + 2/5

Step 1

Find the Least Common Denominator (LCD)

The denominators 9 and 5 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 9 × 5 = 45.

LCD(9, 5) = 45

Step 2

Convert to Equivalent Fractions with Common Denominator 45

Multiply the numerator and denominator of 1/9 by 5, and multiply the numerator and denominator of 2/5 by 9 so both fractions share the common base 45.

1 × 5/9 × 5 = 5/45 and 2 × 9/5 × 9 = 18/45

Step 3

Add the Numerators

Now add the numerators (5 + 18 = 23) and keep the common denominator 45 unchanged.

5 + 18/45 = 23/45

Step 4

Check if the Fraction Can Be Simplified

The Greatest Common Divisor (GCD) of 23 and 45 is 1, confirming that 23/45 cannot be reduced further—it is already in its simplest irreducible form.

23/45

Step 5

Decimal & Percentage Representation

Dividing the numerator 23 by denominator 45 produces a repeating decimal (approximately 0.511111, or 51.1111%).

23 ÷ 45 = 0.511111 (51.1111%)

Visual Representation

The diagram below illustrates 1/9 plus 2/5 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`23/45`
Mixed Number Form	`23/45`
Decimal Form	`0.511111`
Percentage	`51.1111%`

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Frequently Asked Questions

What is 1/9 plus 2/5 as a fraction?

1/9 + 2/5 in simplest fraction form is 23/45.

What is 1/9 plus 2/5 as a decimal?

1/9 + 2/5 converted to a decimal is 0.511111.

What is 1/9 plus 2/5 as a percentage?

1/9 + 2/5 expressed as a percentage is 51.1111%.

Does 1/9 plus 2/5 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.511111...) because the denominator contains prime factors other than 2 and 5.