Why adding is the hard one
Multiplying fractions is straightforward — top times top, bottom times bottom. Dividing is the same thing after flipping the second fraction. Adding and subtracting are where people lose marks, because you cannot combine parts of different sizes: thirds and quarters have to be rewritten as twelfths before anything can be added.
This page uses the product of the denominators as the common denominator, then reduces at the end. Using the LCM instead would keep the intermediate numbers smaller and reach the same final answer.
Lowest terms, mixed numbers, decimals
Every result is reduced by dividing both parts by their greatest common factor, so 6/8 becomes 3/4. Improper fractions are also given as mixed numbers — 7/3 as 2⅓ — because that is usually the form a written answer wants.
The decimal is exact where the fraction allows it and rounded where it does not: 1/3 has no finite decimal form, so what you see is truncated, while the fraction remains exact.
Frequently asked questions
Can I enter negative fractions or whole numbers?
Yes. Put the minus sign on the numerator, and write a whole number over 1. The sign is normalised onto the numerator in the answer, so you will never see a negative denominator.
Is anything uploaded?
No. The arithmetic happens in the page itself.
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