Area of a Rectangle
⏱ 0:26📘 Grade 3 · Area
Cover a 4 cm × 3 cm rectangle with 1 cm² squares: 4 in a row, 3 rows, 12 squares. So area = length × width = 4 × 3 = 12 cm².
The videos are narrated in Mandarin Chinese with on-screen subtitles.
📚 What you will learn
- Area: how big a surface or a closed shape is.
- A square with 1 cm sides has an area of 1 square centimetre (1 cm²).
- A 4 cm × 3 cm rectangle holds 4 squares per row and 3 rows: 12 cm².
- Area of a rectangle = length × width; area of a square = side × side.
🎙️ What the video says (in Chinese)
- 这个长方形到底有多大呢？我们来认识面积！
- 图形的大小，就是它的面积。
- 用边长 1 厘米的小正方形来量，每个是 1 平方厘米。
- 一行摆 4 个，摆 3 行，一共 12 个。
- 所以面积是 12 平方厘米。长 × 宽：4 × 3 = 12！
- 长方形的面积 = 长 × 宽！
✏️ Try it yourself
A rectangle is 6 cm long and 4 cm wide. What is its area?
Show answer
6 × 4 = 24 cm²
A square has 5 cm sides. What is its area?
Show answer
5 × 5 = 25 cm²
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