4 Function Calculator with Fractions
A 4 function calculator with fractions is a basic calculator that adds, subtracts, multiplies, and divides fractions and returns the answer as a fraction instead of only a decimal. The fraction calculator reads a numerator and a denominator for each value, applies the chosen arithmetic operation, and reduces the result to lowest terms.
4 Main Benefits of a Four Function Fraction Calculator
A four function fraction calculator gives 4 main benefits: exact answers with no rounding, automatic simplification, mixed number support, and instant fraction to decimal conversion.
Exact Answers
The answer stays a fraction, with no rounding.
Automatic Simplification
Every result is reduced to lowest terms. To simplify or convert a single fraction, use the Fraction to Decimal Calculator.
Mixed Number Support
Enter a whole number, numerator, and denominator for any value.
Instant Fraction to Decimal
The decimal appears next to the fraction result.
5 Main Parts of the Fraction Calculator
The calculator has 5 main parts.
How to Use This Fraction Calculator
To use this fraction calculator, enter two fractions, pick one of the 4 operations, and press Calculate. The calculator needs 6 steps from input to answer.
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Type the Whole Number (Mixed Numbers Only)
Type the whole number of the first value, if the value is a mixed number. Leave the whole number field blank for proper and improper fractions.
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Enter the Numerator and Denominator
Enter the numerator in the top field and the denominator in the bottom field. The denominator can't be 0.
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Select an Operation
Select addition +, subtraction −, multiplication ×, or division ÷.
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Enter the Second Fraction
Enter the second fraction the same way.
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Press Calculate
Press Calculate to get the answer.
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Read the Result in 3 Formats
Read the result as a simplified fraction, a mixed number, and a decimal.
Fractions on a Physical Calculator
A physical calculator with a fraction key follows the same logic. On the Casio fx-260 Solar and the Texas Instruments (TI) TI-30Xa, the fraction key is labeled a b/c.
How to Add and Subtract Fractions
To add or subtract fractions, rewrite both fractions with a common denominator, then add or subtract the numerators. Fraction addition and fraction subtraction take 4 steps.
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Find the LCD
Find the Least Common Denominator (LCD), which is the Least Common Multiple (LCM) of the two denominators. The GCF and LCM Calculator finds it for you.
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Rewrite the Fractions
Rewrite each value as an equivalent fraction over the LCD.
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Add or Subtract the Numerators
Add or subtract the numerators and keep the denominator.
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Simplify With the GCD
Simplify the result by dividing by the Greatest Common Divisor (GCD).
Addition Example
Different denominators: 4 and 6- Find the LCD: the LCM of 4 and 6 is 12LCD = 12
- Rewrite each fraction over 121/4 = 3/12 · 5/6 = 10/12
- Add the numerators3/12 + 10/12 = 13/12
Subtraction Example
Different denominators: 8 and 3- Find the LCD of 8 and 3LCD = 24
- Rewrite each fraction over 247/8 = 21/24 · 1/3 = 8/24
- Subtract the numerators21/24 − 8/24 = 13/24
How to Multiply and Divide Fractions
Fraction multiplication needs no common denominator, and fraction division is multiplication by the reciprocal of the second fraction.
Multiplying Fractions
No common denominator neededTo multiply fractions, multiply the numerators together and the denominators together. Fraction multiplication needs no common denominator.
- Multiply straight across2/3 × 3/5 = (2 × 3)/(3 × 5) = 6/15
- Simplify6/15 = 2/5
Dividing Fractions
Flip the second fraction, then multiplyTo divide fractions, multiply the first fraction by the reciprocal of the second fraction. The reciprocal flips the numerator and denominator.
- Multiply by the reciprocal of 2/53/4 ÷ 2/5 = 3/4 × 5/2
- Multiply straight across3/4 × 5/2 = 15/8
Real-World Example: Cutting a Board
Division answers "how many fit" questions. A 6-foot (1.83 m) board cut into 3/4-foot (9 in, 22.86 cm) pieces gives 8 pieces.
Working With Mixed Numbers and Simplifying
To work with mixed numbers, convert each mixed number to an improper fraction before the calculation.
Mixed Number → Improper Fraction
Multiply the whole number by the denominator, add the numerator, and place the total over the original denominator.
Multiplying Mixed Numbers
A full mixed number example: convert both values to improper fractions, multiply, simplify, and write the answer as a mixed number.
Simplifying Fractions
Divide the numerator and denominator by their GCD. A fraction is fully simplified when the GCD of the numerator and denominator is 1.
Improper Fraction → Mixed Number
Divide the numerator by the denominator. The quotient is the whole number and the remainder is the new numerator.
Fraction Keys on Elementary Calculators
Elementary fraction calculators handle these conversions with dedicated keys.
Simp Key
The Texas Instruments TI-15 Explorer has a Simp key that reduces fractions step by step.
U n/d Key
The TI-15 Explorer's U n/d key switches between mixed numbers and improper fractions.
Casio fx-55 Plus
The Casio fx-55 Plus offers similar fraction entry for elementary classrooms.
Fraction Formulas for All Four Operations
There are 4 fraction formulas, one for each arithmetic operation. In each formula, a/b and c/d are fractions with nonzero denominators.
| Operation | Formula | Example |
|---|---|---|
| Addition | a/b + c/d = (ad + bc)/(bd) |
1/2 + 1/3 = 5/6 |
| Subtraction | a/b − c/d = (ad − bc)/(bd) |
3/4 − 1/6 = 7/12 |
| Multiplication | a/b × c/d = ac/bd |
2/3 × 3/5 = 2/5 |
| Division | a/b ÷ c/d = ad/bc (c ≠ 0) |
3/4 ÷ 2/5 = 15/8 |
3 Supporting Formulas
3 supporting formulas complete the set.
Mixed to Improper
Fraction to Decimal
Fraction to Percentage
Order of Operations With Fractions
Expressions with more than one operation follow the order of operations: Parentheses, Exponents, Multiplication, Division, Addition, Subtraction (PEMDAS).
- PParentheses
- EExponents
- MMultiplication
- DDivision
- AAddition
- SSubtraction
Explore Other Calculators
Select the specialized calculation tool tailored for your specific mathematical needs.
Frequently Asked Questions
Can a 4 function calculator do fractions?
Yes, a 4 function calculator does fractions when the calculator has a fraction key, and any 4 function calculator handles fractions as decimals. A standard calculator with no fraction button converts 3/4 to 0.75 when you enter 3 ÷ 4.
Calculators with a fraction key keep the answer in fraction form, including the Casio fx-55 Plus, the Texas Instruments TI-15 Explorer, the Casio fx-260 Solar, and the Texas Instruments TI-30Xa. Scientific calculators such as the Texas Instruments TI-34 MultiView and the Casio fx-300ES Plus show fractions in textbook format. Online tools, including Desmos, Wolfram Alpha, and GeoGebra, return exact fraction results.
How do you enter a fraction on a basic calculator?
To enter a fraction on a basic calculator, divide the numerator by the denominator. For 5/8, press 5 ÷ 8 = to get 0.625.
On a calculator with a fraction key, press the numerator, the a b/c key, and the denominator. For a mixed number such as 2 5/8, press 2, a b/c, 5, a b/c, 8. Graphing calculators use menu commands: the TI-84 Plus converts a decimal answer with Math, then ►Frac.
Does this calculator work with mixed numbers?
Yes, this calculator works with mixed numbers in all 4 operations. Enter the whole number, numerator, and denominator in separate fields, and the calculator converts the mixed number to an improper fraction before the calculation. The result appears as a simplified improper fraction and a mixed number, so 1 1/2 + 2 3/4 shows 17/4 and 4 1/4.
Can I convert the answer to a decimal?
Yes, the calculator shows every answer as a decimal next to the fraction result. 7/8 displays as 0.875, and repeating decimals such as 1/3 display as 0.3333. To get a percentage, multiply the decimal by 100: 7/8 = 87.5%.
Physical calculators switch formats with a conversion key, such as the F↔D key on the TI-30Xa or the S⇔D key on the Casio fx-300ES Plus.
Start Calculating Fractions Now
Use this free online 4 function calculator with fractions. Add, subtract, multiply, and divide with automatic simplification and decimal conversion.
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