Basic Math

Fraction Calculator

Combines two fractions and always gives an exact result in lowest terms. Write fractions as 3/4, whole numbers as 5, or mixed numbers as 1 3/4. Choose “Simplify” to reduce the first fraction on its own.

Inputsa/b ∘ c/d

First fractionOperationSecond fraction

Step-by-step

waiting

Fill in the fields and press Solve. The full method will appear here, one numbered step at a time.

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Worked example

Add 3/4 and 5/6, giving the answer as a simplified fraction.

1.
Find the lowest common denominator of the two fractions.
```
LCD(4, 6) = 12
```
2.
Rewrite each fraction over that denominator.
```
3/4 = 9/12,   5/6 = 10/12
```
3.
Add the numerators and keep the denominator.
```
9 + 10 = 19, giving 19/12
```

Answer: 19/12

Note: Works with fractions, whole numbers and decimals; a denominator of 0 is rejected.

Use “Load worked example” above to run this in the solver.

Related formulas

The formulas this tool uses, each explained with symbols, conditions and its own example in the Formula Library.

Adding fractionsa/b + c/d = (a·d + c·b) ÷ (b·d)