FRACTIONS
Fraction math, auto-simplified.
Add, subtract, multiply and divide fractions with auto-simplification, mixed numbers and steps.
12 + 13 = 56 = 0.8333
通分后计算，结果约去最大公约数 1 得最简分数。
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Solution animation · visualize fractions
Fractions 1/2 and 1/3
What is this?
Enter two fractions and an operator, click “Calculate” to get the simplest fraction, decimal and mixed number, with key steps shown.
示例与注意事项Example & notes
一个例子A worked example
算 2/3 + 1/4：通分得 8/12 + 3/12 = 11/12，页面同时画出条形图，能直观看到为什么要通分。Compute 2/3 + 1/4: convert to 8/12 + 3/12 = 11/12, with a bar diagram showing why common denominators are needed.
注意事项Things to watch
- 结果自动约分到最简，可切换成带分数显示（11/8 → 1 3/8）。Results reduce to lowest terms automatically and can be shown as mixed numbers.
- 除数为 0 会明确报错，不会返回无穷大这种无意义结果。Dividing by zero raises an explicit error instead of returning infinity.
- 通分只用于加减法；乘除直接分子分母分别运算，不需要通分。Common denominators are only needed for addition and subtraction — multiply and divide directly.
相关问答More Q&A
能展示计算过程吗？Does it show the working?
可以，动画模式会逐步演示通分、运算与约分，适合讲给孩子看。Yes — the animation walks through finding the denominator, computing and reducing.
支持带分数输入吗？Can I enter mixed numbers?
支持，输入 1 2/3 即表示一又三分之二，负数也支持。Yes — 1 2/3 means one and two thirds; negatives work too.