Fraction Calculator

Type fractions like 3/4 or mixed numbers like 1 1/2. Every answer is exact and in lowest terms.

Result
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    How it works

    The method

    To add or subtract, write the fractions over a common bottom number (the least common multiple), then add the top numbers. To multiply, multiply tops and bottoms; to divide, multiply by the flipped fraction. Simplify by the greatest common divisor.

    Worked example

    1/2 + 1/3 = 3/6 + 2/6 = 5/6. 3/4 ÷ 1/2 = 3/4 × 2/1 = 6/4 = 3/2 = 1 1/2.

    Common mistakes

    Adding tops and bottoms (1/2 + 1/3 = 2/5) is wrong. A whole number such as 3 is the fraction 3/1.

    Questions & answers

    How do I type a mixed number like one and a half?

    Type the whole number, a space, then the fraction: 1 1/2. For a minus sign put it in front: -1 1/2. A whole number like 5 or a decimal like 0.75 also works.

    It says “Write a fraction like 3/4”. What is wrong?

    Use only digits, one / and, for a mixed number, one space. The top and bottom must be whole numbers: 1.5/2 is not accepted — write 3/4 instead.

    How do I add fractions with different bottom numbers?

    Make the bottoms the same first: 1/2 + 1/3 = 3/6 + 2/6 = 5/6. The calculator shows this step with the smallest common bottom number.

    Why is my answer shown as 3/2 and as 1 1/2?

    Both are the same number. 3/2 is the improper fraction and 1 1/2 is the mixed number; use the one your teacher or recipe asks for.

    How do I turn 0.375 into a fraction?

    Open Decimal → fraction and type 0.375. Three decimal places means 375/1000, and dividing top and bottom by 125 gives 3/8.

    How do I know which fraction is bigger?

    Open Compare and type both. 3/5 = 24/40 and 5/8 = 25/40, so 5/8 is bigger, by 1/40. The steps show the common bottom number.

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