What is 18/38 plus 9/13? (Answer: 288/247)

Exact Answer

==================================================
Problem: What is 18/38 plus 9/13?
Formula / Expression: 18/38 + 9/13
Final Answer: 1 41/247 (288/247)
==================================================

Step-by-Step Solution:

Step 1: Find the Least Common Denominator (LCD)
The denominators 38 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 38 × 13 = 494.
Working: LCD(38, 13) = 494

Step 2: Convert to Equivalent Fractions with Common Denominator 494
Multiply the numerator and denominator of 18/38 by 13, and multiply the numerator and denominator of 9/13 by 38 so both fractions share the common base 494.
Working: 18 × 13/38 × 13 = 234/494 and 9 × 38/13 × 38 = 342/494

Step 3: Add the Numerators
Now add the numerators (234 + 342 = 576) and keep the common denominator 494 unchanged.
Working: 234 + 342/494 = 576/494

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 576 and 494, which is 2. Divide both the numerator and denominator by 2.
Working: 576 ÷ 2/494 ÷ 2 = 288/247

Step 5: Convert Improper Fraction to a Mixed Number
Since the numerator (288) is greater than the denominator (247), divide 288 by 247: it goes in 1 whole time(s) with a remainder of 41, giving the mixed number 1 41/247.
Working: 288/247 = 1 41/247

Step 6: Decimal & Percentage Representation
Dividing the numerator 288 by denominator 247 produces a repeating decimal (approximately 1.165992, or 116.5992%).
Working: 288 ÷ 247 = 1.165992 (116.5992%)

Key Values:
- Simplified Fraction: 288/247
- Mixed Number Form: 1 41/247
- Decimal Value: 1.165992
- Percentage: 116.5992%

--------------------------------------------------
Solved with FractionsCalc:
https://fractionscalc.com/what-is-18-38-plus-9-13/
==================================================

18/38 + 9/13 = 288/247

Simplified Fraction

288/247

Mixed Number

1 41/247

Decimal Value

1.165992

Percentage

116.5992%

Reduce / Convert Fraction:

Convert Fraction:

Enter Decimal Number:

Enter Percentage: %

What is % of

From Value: To Value:

Simplify Ratio: :

Switch to Proportion / Missing X Solver (A/B = C/D) →

Enter 3 known numbers and leave 1 empty (or type x) to solve:

← Switch to Ratio Simplifier (A:B)

Provide any 2 values below to calculate the remaining:

Price before discount

Discount

Price after discount

You saved

+ Add Sales Tax & Extra Coupon (Optional)

Sales Tax: % Extra Off: %

Provide any 2 values below to calculate the remaining:

Cost

Markup

REVENUE

Gross Profit

Profit Margin

Bill Subtotal

Tip Percentage

Split (People)

👥

Quick Tip:

Total Bill

Split Between

👥

Tip % (Optional)

Include Tip:

Total Price

Quantity

Unit of Measure

← Discount & Sales Tax • Ratio Simplifier (A:B) →

First Number: Second Number:

Find All Factors of:

Dividend: ÷ Divisor:

Number to Round: To Nearest:

Method: Standard (5+ ↑) Always Up (Ceil) Always Down (Floor)

Presets:

√ Square Root of: OR Power (x^y): ^{^}

x² + x + = 0

Number (n! & log):

Circle Radius (r):

Side a: Side b:

Angle (Degrees): °

Numbers (comma separated):

Total Items (n): Choose (r):

Decimal Number:

Number (1–3999):

Step-by-Step Solution: 18/38 + 9/13

Step 1

Find the Least Common Denominator (LCD)

The denominators 38 and 13 are coprime (they share no common factors other than 1). Therefore, their Least Common Denominator (LCD) is simply their direct product: 38 × 13 = 494.

LCD(38, 13) = 494

Step 2

Convert to Equivalent Fractions with Common Denominator 494

Multiply the numerator and denominator of 18/38 by 13, and multiply the numerator and denominator of 9/13 by 38 so both fractions share the common base 494.

18 × 13/38 × 13 = 234/494 and 9 × 38/13 × 38 = 342/494

Step 3

Add the Numerators

Now add the numerators (234 + 342 = 576) and keep the common denominator 494 unchanged.

234 + 342/494 = 576/494

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 576 and 494, which is 2. Divide both the numerator and denominator by 2.

576 ÷ 2/494 ÷ 2 = 288/247

Step 5

Convert Improper Fraction to a Mixed Number

Since the numerator (288) is greater than the denominator (247), divide 288 by 247: it goes in 1 whole time(s) with a remainder of 41, giving the mixed number 1 41/247.

288/247 = 141/247

Step 6

Decimal & Percentage Representation

Dividing the numerator 288 by denominator 247 produces a repeating decimal (approximately 1.165992, or 116.5992%).

288 ÷ 247 = 1.165992 (116.5992%)

Visual Representation

The diagram below illustrates 18/38 plus 9/13 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`288/247`
Mixed Number Form	`1 41/247`
Decimal Form	`1.165992`
Percentage	`116.5992%`

Was this solution helpful?

Help us improve our free step-by-step tools

Frequently Asked Questions

What is 18/38 plus 9/13 as a fraction?

18/38 + 9/13 in simplest fraction form is 288/247 (or 1 41/247 as a mixed number).

What is 18/38 plus 9/13 as a decimal?

18/38 + 9/13 converted to a decimal is 1.165992.

What is 18/38 plus 9/13 as a percentage?

18/38 + 9/13 expressed as a percentage is 116.5992%.

How do you write 18/38 plus 9/13 as a mixed number?

Because the numerator is greater than the denominator, the improper fraction 288/247 can be written as the mixed number 1 41/247.

Does 18/38 plus 9/13 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 1.165992...) because the denominator contains prime factors other than 2 and 5.