Fraction Calculator

Add, subtract, multiply, and divide proper fractions, improper fractions, and mixed numbers. Features automatic LCD computation, Keep-Change-Flip steps, and irreducible lowest terms.

Fraction Math Solver

First Fraction
Second Fraction

Calculation Result Solved

Simplified Result
$$ \frac{17}{12} = 1\frac{5}{12} $$
Improper Fraction & Mixed Number
Decimal Value
1.4167
Percentage
141.67%
Reciprocal
12/17
GCD Simplified
1 (Irreducible)

Mathematical Step-by-Step Proof

How to Use the All-in-One Fraction Calculator

This calculator solves any mathematical expression between two fractions or mixed numbers with full arithmetic transparency. Whether working on school homework, adjusting culinary recipes, or computing structural dimensions, follow these simple steps:

1

Enter Values

Enter whole numbers (if any), numerators, and denominators for both fractions.

2

Select Operator

Choose between Addition (+), Subtraction (-), Multiplication (×), or Division (÷).

3

Compute Steps

The calculator automatically applies LCD unification or reciprocal division.

4

Review Proof

Inspect the irreducible fraction, mixed number, decimal value, and step proof.

Core Arithmetic Rules for Fractions

1. Addition & Subtraction (Common Denominator)

To add or subtract fractions, you must find a common denominator (LCD) before operating on numerators:

$$ \frac{a}{b} \pm \frac{c}{d} = \frac{a \cdot d \pm b \cdot c}{b \cdot d} $$

2. Multiplication (Straight Across)

Multiply numerators together and denominators together without needing a common denominator:

$$ \frac{a}{b} \times \frac{c}{d} = \frac{a \times c}{b \times d} $$

3. Division (Keep-Change-Flip)

Multiply the first fraction by the multiplicative inverse (reciprocal) of the second fraction:

$$ \frac{a}{b} \div \frac{c}{d} = \frac{a}{b} \times \frac{d}{c} = \frac{a \times d}{b \times c} $$

4. Mixed Number Conversion

Convert any mixed number into an improper fraction before multiplication or division:

$$ W\frac{N}{D} = \frac{W \times D + N}{D} $$

Worked Step-by-Step Examples

Example 1: Adding Mixed Numbers (1 1/2 + 2 1/3)

Convert to improper fractions: 3/2 and 7/3. Least Common Multiple of denominators 2 and 3 is 6.

3/2 + 7/3 = 9/6 + 14/6 = 23/6 = 3 5/6 (approx 3.8333)
Example 2: Dividing Fractions with Cross-Cancellation (5/6 ÷ 10/21)

Keep 5/6, change ÷ to ×, and flip 10/21 to 21/10. Cross-cancel 5 with 10 (factor 5) and 21 with 6 (factor 3):

(5/6) × (21/10) = (1/2) × (7/2) = 7/4 = 1 3/4 (1.75)

Problems Solved by the Universal Fraction Calculator

Eliminating Denominator Confusion

Students frequently try to add or subtract numerators and denominators straight across (e.g. 1/2 + 1/3 = 2/5). This calculator shows the necessary LCD scaling step, preventing this common error.

Mixed Number Operations without FOIL

Direct multiplication of mixed numbers like 2 1/2 × 3 1/4 requires awkward algebraic expansions. Converting to improper fractions first streamlines computation into direct multiplication.

Keep-Change-Flip Division Logic

Clearly displays the reciprocal transformation step during division, demonstrating why dividing by a fraction is identical to multiplying by its inverse.

Carpentry & Trade Blueprint Scaling

Combines fractional dimensions like adding 5 5/8 in to 11 3/16 in with instant irreducible fractional results and decimal equivalents.

Key Features & Calculation Capabilities

Full 4-Operation Suite

Add, subtract, multiply, and divide proper fractions, improper fractions, and mixed numbers in real time.

Dynamic LCD & Cross-Cancellation

Computes Least Common Denominators for addition/subtraction and performs cross-cancellation during multiplication.

Multi-Format Solutions

Displays simplest proper/improper fraction, mixed number, 4-decimal value, percentage, and reciprocal.

Operations Comparison Matrix

Operation Requires Common Denominator? Primary Rule Example Result
Addition (+) Yes (LCD required) Scale denominators, add numerators 1/4 + 1/2 = 3/4
Subtraction (-) Yes (LCD required) Scale denominators, subtract numerators 5/6 - 1/3 = 1/2
Multiplication (×) No Multiply straight across, cross-cancel 2/3 × 3/5 = 2/5
Division (÷) No Keep-Change-Flip, multiply by reciprocal 3/4 ÷ 2/3 = 9/8 = 1 1/8

Frequently Asked Questions

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