小数和分数（11岁及以上）
Decimals and fractions (age 11+)
能够互换使用有限小数及其对应的分数（如 3.5 和 7/2，或 0.375 和 3/8）；并能在两种形式之间熟练转换。
Work interchangeably with terminating decimals and their corresponding fractions (such as 3.5 and 7/2 or 0.375 and 3/8); convert fluently between the two forms
学习证据 / Evidence
- 将任意有限小数转换为最简分数
- 将分母的质因数仅为 2 和 5 的分数转换为有限小数
- 解释为什么有些分数能化成有限小数，而有些不能
- Convert any terminating decimal to a fraction in simplest form
- Convert any fraction with a denominator whose prime factors are only 2 and 5 to a terminating decimal
- Explain why some fractions produce terminating decimals and others do not
评估问题 / Assessment
如果 {{name}} 在计算器屏幕上看到 0.375，能否在不使用计算器的情况下把它转换为最简分数？
If {{name}} sees 0.375 on a calculator display, can they convert it to a fraction in its simplest form — without using the calculator?