What is 7/18 plus 4/9? (Answer: 5/6)

Exact Answer

==================================================
Problem: What is 7/18 plus 4/9?
Formula / Expression: 7/18 + 4/9
Final Answer: 5/6
==================================================

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 7/18 by 1, and multiply the numerator and denominator of 4/9 by 2 so both fractions share the common base 18.
Working: 7 × 1/18 × 1 = 7/18 and 4 × 2/9 × 2 = 8/18

Step 3: Add the Numerators
Now add the numerators (7 + 8 = 15) and keep the common denominator 18 unchanged.
Working: 7 + 8/18 = 15/18

Step 4: Simplify the Fraction to Lowest Terms
Find the Greatest Common Divisor (GCD) of 15 and 18, which is 3. Divide both the numerator and denominator by 3.
Working: 15 ÷ 3/18 ÷ 3 = 5/6

Step 5: Decimal & Percentage Representation
Dividing the numerator 5 by denominator 6 produces a repeating decimal (approximately 0.833333, or 83.3333%).
Working: 5 ÷ 6 = 0.833333 (83.3333%)

Key Values:
- Simplified Fraction: 5/6
- Mixed Number Form: 5/6
- Decimal Value: 0.833333
- Percentage: 83.3333%

--------------------------------------------------
Solved with FractionsCalc:
https://fractionscalc.com/what-is-7-18-plus-4-9/
==================================================

7/18 + 4/9 = 5/6

Simplified Fraction

5/6

Mixed Number

Proper (5/6)

Decimal Value

0.833333

Percentage

83.3333%

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: 7/18 + 4/9

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 7/18 by 1, and multiply the numerator and denominator of 4/9 by 2 so both fractions share the common base 18.

7 × 1/18 × 1 = 7/18 and 4 × 2/9 × 2 = 8/18

Step 3

Add the Numerators

Now add the numerators (7 + 8 = 15) and keep the common denominator 18 unchanged.

7 + 8/18 = 15/18

Step 4

Simplify the Fraction to Lowest Terms

Find the Greatest Common Divisor (GCD) of 15 and 18, which is 3. Divide both the numerator and denominator by 3.

15 ÷ 3/18 ÷ 3 = 5/6

Step 5

Decimal & Percentage Representation

Dividing the numerator 5 by denominator 6 produces a repeating decimal (approximately 0.833333, or 83.3333%).

5 ÷ 6 = 0.833333 (83.3333%)

Visual Representation

The diagram below illustrates 7/18 plus 4/9 visually:

Summary & Alternative Representations

Property / Format	Value
Lowest Terms Fraction	`5/6`
Mixed Number Form	`5/6`
Decimal Form	`0.833333`
Percentage	`83.3333%`

Was this solution helpful?

Help us improve our free step-by-step tools

Frequently Asked Questions

What is 7/18 plus 4/9 as a fraction?

7/18 + 4/9 in simplest fraction form is 5/6.

What is 7/18 plus 4/9 as a decimal?

7/18 + 4/9 converted to a decimal is 0.833333.

What is 7/18 plus 4/9 as a percentage?

7/18 + 4/9 expressed as a percentage is 83.3333%.

Does 7/18 plus 4/9 result in a terminating or repeating decimal?

It results in a repeating decimal (approximately 0.833333...) because the denominator contains prime factors other than 2 and 5.