What is 1/9 plus 4/9?
1/9 plus 4/9 equals 5/9 (or 0.555556 in decimal form). Learn the step-by-step solution to add 1/9 and 4/9 using Least Common Denominator and simplification.
Exact Answer
1/9 + 4/9 = 5/9
Simplified Fraction
5/9
Mixed Number
Proper (5/9)
Decimal Value
0.555556
Percentage
55.5556%
Step-by-Step Solution: 1/9 + 4/9
Step 1
Check the Denominators (Like Fractions)
Both fractions already share the identical denominator (9). Because these are like fractions, no conversion to a common denominator is required—we directly add their numerators while keeping the denominator 9.
1/9 + 4/9
Step 2
Add the Numerators
Now add the numerators (1 + 4 = 5) and keep the common denominator 9 unchanged.
1 + 4/9 = 5/9
Step 3
Check if the Fraction Can Be Simplified
The Greatest Common Divisor (GCD) of 5 and 9 is 1, confirming that 5/9 cannot be reduced further—it is already in its simplest irreducible form.
5/9
Step 4
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 1/9 plus 4/9 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 1/9 plus 4/9 as a fraction?
1/9 + 4/9 in simplest fraction form is 5/9.
What is 1/9 plus 4/9 as a decimal?
1/9 + 4/9 converted to a decimal is 0.555556.
What is 1/9 plus 4/9 as a percentage?
1/9 + 4/9 expressed as a percentage is 55.5556%.
Does 1/9 plus 4/9 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.