Fraction Calculator

Add, subtract, multiply, and divide fractions and mixed numbers with step-by-step solutions. Simplify fractions to lowest terms, convert between decimals and fractions, and see results as fractions, mixed numbers, decimals, and percentages. Includes visual fraction representations and detailed formula breakdowns.

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11
12

11 of 12 equal parts

Mixed:11/12Decimal:0.917Percent:91.667%

Step-by-Step Solution

See how the answer is calculated

1.Expression: 3/4 + 1/6
2.Find LCD of 4 and 6: 12
3.3/4 = 9/12
4.1/6 = 2/12
5.9/12 + 2/12 = 11/12

What Is a Fraction?

Understanding numerators, denominators, and fraction types

A fraction represents a part of a whole. It consists of two numbers separated by a line: the numerator (top number) tells how many parts you have, and the denominator (bottom number) tells how many equal parts the whole is divided into. For example, 3/4 means 3 out of 4 equal parts.

Fraction Structure

Numerator / Denominator = Part / Whole

Proper fraction: Numerator is less than denominator (e.g., 3/4, 1/2). Value is less than 1.

Improper fraction: Numerator is greater than or equal to denominator (e.g., 7/4, 5/3). Value is 1 or greater.

Mixed number: A whole number combined with a proper fraction (e.g., 1 3/4, 2 1/3). An improper fraction expressed differently.

How to Add and Subtract Fractions

Find a common denominator, then combine numerators

Same Denominator

When fractions share the same denominator, simply add or subtract the numerators and keep the denominator the same.

2/7 + 3/7 = (2 + 3)/7 = 5/7

Different Denominators

Find the Least Common Denominator (LCD), convert each fraction, then add or subtract.

1/4 + 1/6

LCD of 4 and 6 = 12

3/12 + 2/12 = 5/12

General Formula

a/b + c/d = (a×d + c×b) / (b×d)

How to Multiply Fractions

Multiply straight across — numerator by numerator, denominator by denominator

Multiplying fractions is the simplest operation: multiply the numerators together and the denominators together. No common denominator needed. Then simplify the result.

a/b × c/d = (a×c) / (b×d)

Example:

2/3 × 4/5 = (2×4) / (3×5) = 8/15

Tip: You can simplify (cross-cancel) before multiplying to keep numbers smaller. For example, in 4/9 × 3/8, the 4 and 8 share a factor of 4, and the 3 and 9 share a factor of 3, giving 1/3 × 1/2 = 1/6.

How to Divide Fractions

Flip the second fraction and multiply

To divide fractions, multiply the first fraction by the reciprocal (flip) of the second. This is often remembered as “keep, change, flip”: keep the first fraction, change division to multiplication, flip the second fraction.

a/b ÷ c/d = a/b × d/c = (a×d) / (b×c)

Example:

3/4 ÷ 2/5 = 3/4 × 5/2 = 15/8 = 1 7/8

How to Simplify Fractions

Reduce to lowest terms using the GCD

A fraction is in simplest form when the numerator and denominator share no common factor other than 1. To simplify, find the Greatest Common Divisor (GCD) of both numbers, then divide both by it.

Example: Simplify 18/24

GCD of 18 and 24 = 6

18 ÷ 6 = 3, 24 ÷ 6 = 4

18/24 = 3/4

Converting Between Decimals and Fractions

Switch between decimal and fraction notation

Decimal → Fraction

  • 1. Count decimal places
  • 2. Write over a power of 10
  • 3. Simplify using GCD
  • 0.75 = 75/100 = 3/4

Fraction → Decimal

  • Divide numerator by denominator
  • 3/8 = 3 ÷ 8 = 0.375
  • 1/3 = 1 ÷ 3 = 0.333...

Real-World Examples

How fractions appear in everyday life

Cooking & Recipes

A recipe calls for 2/3 cup of flour but you want to make 1.5 batches. How much flour?

2/3 × 3/2 = 6/6 = 1 cup

Construction & Measurement

A board is 5/8 inch thick. You need to stack 3 boards. Total thickness:

5/8 × 3 = 15/8 = 1 7/8 inches

Time & Scheduling

You studied 3/4 hour in the morning and 1/2 hour at night. Total:

3/4 + 1/2 = 3/4 + 2/4 = 5/4 = 1 1/4 hours

Finance

You own 1/4 of a business. Your partner sells you 1/6 of the company. You now own:

1/4 + 1/6 = 3/12 + 2/12 = 5/12

Common Mistakes When Working with Fractions

Pitfalls to avoid for accurate results

1

Adding numerators and denominators separately

1/2 + 1/3 is NOT 2/5. You must find a common denominator first: 3/6 + 2/6 = 5/6.

2

Forgetting to simplify the final answer

Always check if the result can be reduced by finding the GCD of numerator and denominator.

3

Not converting mixed numbers to improper fractions

For operations, first convert: 2 1/3 = 7/3.

4

Canceling across addition or subtraction

Cross-cancellation only works with multiplication. You cannot cancel the 3s in 3/7 + 1/3.

5

Dividing instead of multiplying by the reciprocal

To divide by a fraction, flip the second fraction and multiply. Never divide numerator by numerator.

Frequently Asked Questions

Common questions about fractions, operations, and conversions