What is 18/39 plus 7/13? (Answer: 1)

Exact Answer

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Problem: What is 18/39 plus 7/13?
Formula / Expression: 18/39 + 7/13
Final Answer: 1
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Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
Notice that 39 is an exact multiple of 13 (13 × 3 = 39). The Least Common Denominator (LCD) is simply 39, meaning we only need to scale one fraction.
Working: LCD(39, 13) = 39

Step 2: Convert to Equivalent Fractions with Common Denominator 39
Multiply the numerator and denominator of 18/39 by 1, and multiply the numerator and denominator of 7/13 by 3 so both fractions share the common base 39.
Working: 18 × 1/39 × 1 = 18/39 and 7 × 3/13 × 3 = 21/39

Step 3: Add the Numerators
Now add the numerators (18 + 21 = 39) and keep the common denominator 39 unchanged.
Working: 18 + 21/39 = 39/39

Step 4: Simplify to an Exact Whole Number
Notice that the numerator (39) is completely divisible by the denominator (39). Dividing 39 by 39 yields the whole number 1 with zero remainder.
Working: 39/39 = 1

Step 5: Decimal & Percentage Representation
Dividing the numerator 1 by denominator 1 yields an exact terminating decimal of 1 (or 100%).
Working: 1 ÷ 1 = 1 (100%)

Key Values:
- Simplified Fraction: 1
- Mixed Number Form: 1
- Decimal Value: 1
- Percentage: 100%

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Solved with FractionsCalc:
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18/39 + 7/13 = 1

Simplified Fraction

Mixed Number

Decimal Value

Percentage

100%

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Step-by-Step Solution: 18/39 + 7/13

Step 1

Find the Least Common Denominator (LCD)

Notice that 39 is an exact multiple of 13 (13 × 3 = 39). The Least Common Denominator (LCD) is simply 39, meaning we only need to scale one fraction.

LCD(39, 13) = 39

Step 2

Convert to Equivalent Fractions with Common Denominator 39

Multiply the numerator and denominator of 18/39 by 1, and multiply the numerator and denominator of 7/13 by 3 so both fractions share the common base 39.

18 × 1/39 × 1 = 18/39 and 7 × 3/13 × 3 = 21/39

Step 3

Add the Numerators

Now add the numerators (18 + 21 = 39) and keep the common denominator 39 unchanged.

18 + 21/39 = 39/39

Step 4

Simplify to an Exact Whole Number

Notice that the numerator (39) is completely divisible by the denominator (39). Dividing 39 by 39 yields the whole number 1 with zero remainder.

39/39 = 1

Step 5

Decimal & Percentage Representation

Dividing the numerator 1 by denominator 1 yields an exact terminating decimal of 1 (or 100%).

1 ÷ 1 = 1 (100%)

Visual Representation

The diagram below illustrates 18/39 plus 7/13 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`1`
Mixed Number Form	`1`
Decimal Form	`1`
Percentage	`100%`

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Frequently Asked Questions

What is 18/39 plus 7/13 as a fraction?

18/39 + 7/13 in simplest fraction form is 1.

What is 18/39 plus 7/13 as a decimal?

18/39 + 7/13 converted to a decimal is 1.

What is 18/39 plus 7/13 as a percentage?

18/39 + 7/13 expressed as a percentage is 100%.

Is the answer to 18/39 plus 7/13 a whole number?

Yes, 18/39 + 7/13 simplifies completely to the whole number 1 with no remaining fractional part.