用条形模型表示比
Bar Models for Ratios
用条形模型（分成等份并标有数量的矩形条）和带状图（展示部分与部分、部分与整体关系的分段条）来表示比和比例问题；借助这些可视化模型来建立并解决不等量分配、按比例缩放和百分比问题——先画图，再从图中读出答案。
Represent ratio and proportion problems using bar models (rectangular strips divided into equal parts labelled with quantities) and tape diagrams (segmented strips showing part-to-part and part-to-whole relationships); use these visual models to set up and solve unequal sharing, scaling, and percentage problems — drawing the diagram first, then reading off the answer
学习证据 / Evidence
- 画条形模型来表示一个比的问题——例如，按3:2的比分20英镑，画出5个相等的方块。
- 用条形模型解决比例问题，并说明每一步。
- 将条形模型与其他表示方式（表格、双重数轴）进行比较，并说明各自最适用的场景。
- Draw a bar model to represent a ratio problem — e.g. sharing £20 in the ratio 3:2 by drawing 5 equal blocks
- Use a bar model to solve a proportion problem and explain each step
- Compare bar models with other representations (tables, double number lines) and explain when each is most useful
评估问题 / Assessment
如果{{name}}需要按2:3的比把30张贴纸分给两个朋友，能画出一个条形模型——把一条分成5个相等的格子——并用它算出每人各得多少，而不是只靠猜吗？
If {{name}} needs to share 30 stickers between two friends in a 2:3 ratio, can they draw a bar model — splitting a strip into 5 equal boxes — and use it to work out each share without just guessing?