Fraction calculator
Do the four operations, simplify fractions and convert to or from decimals. Check your working here; for a full step-by-step derivation, paste the sum into the MathsGPT solver.
Basic Operations
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Example: 1/2 + 1/4 = 3/4
Simplification
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Example: 21/98 = 3/14
Decimal to Fraction
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Example: 1.375 = 11/8
Fraction to Decimal
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Large Fraction Calculator
Use this when the numerators or denominators are large whole numbers.
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Fraction guide
Handles the four operations, simplification, mixed numbers and fraction–decimal conversion. Use it to check answers; for full working, use the solver.
Rules
- Addition/Subtraction: same denominator, then add/subtract numerators.
- Different denominators: find LCM for a common denominator.
- Multiplication: numerator times numerator, denominator times denominator.
- Division: multiply by the reciprocal of the second fraction.
- Simplify: divide by GCD.
Conversions
- Fraction → Decimal: numerator ÷ denominator.
- Decimal → Fraction: write as power of ten, then simplify.
- Mixed number: 2 1/4 = (2 × 4 + 1) / 4 = 9/4.
Example calculations
7/3 + 5/3 = 4.
1/4 + 1/5 → LCM 20 → 5/20 + 4/20 = 9/20.
18/24 = 3/4 (GCD 6).
3/8 = 0.375.
2 2/5 = 12/5.
Common pitfalls
- Adding the denominators instead of finding a common denominator first.
- Not simplifying the answer (cancel common factors).
- Reversing numerator and denominator when converting to decimal.
Where fractions turn up
- Recipes, measures and scaling (halves, quarters).
- Geometry with fractional lengths or areas.
- Sharing and proportionality.
Quick answers
- Wrong answer? Check you’ve used a common denominator and simplified.
- Mixed numbers? Enter as e.g. "2 3/4" (whole number, space, fraction).
- For full step-by-step working, paste your expression into the main solver.