Length and distance (II)
The centimetre (cm); measuring the length of objects and the distance between two points with a ruler, including when the object does not start at 0; choosing a suitable measuring tool; and estimating lengths with ever-ready rulers such as the width of a thumb, the length of a foot or a hand span.
Key words
| Chinese | English |
|---|---|
| 厘米 | centimetre (cm) |
| 間尺 | ruler |
| 量度 | measure |
| 估計 | estimate |
The 4 short lessons and the chapter test
Lessons are in Chinese for now.
- 認識厘米尺
- 量度距離
- 揀選工具和永備尺
- 估計長度
- 章節測驗 (chapter test)
Sample questions (in Chinese)
Question 1這枝鉛筆長多少厘米?
cm
Answer and explanation
答案:5 cm
為甚麼?一端對準 0,另一端對準 5,所以長 5 厘米,寫作 5 cm。
Question 2這枝鉛筆沒有對準 0。它長多少厘米?
cm
Answer and explanation
答案:4 cm
為甚麼?一端對準 3,另一端對準 7。由 3 數到 7,共有 4 格,每格 1 厘米,所以長 4 cm。
Question 3兩點之間的距離是多少厘米?
cm
Answer and explanation
答案:3 cm
為甚麼?一點對準 1,另一點對準 4。由 1 數到 4,共有 3 格,所以距離是 3 cm。
Question 4紙帶乙長 13 cm,紙帶甲長 8 cm。紙帶乙比紙帶甲長多少厘米?
長 cm
Answer and explanation
答案:長 5 cm
為甚麼?求相差多少,用減法:13 − 8 = 5,所以紙帶乙比紙帶甲長 5 cm。
Based on learning unit 1M3 of the Education Bureau’s Primary Mathematics Curriculum (2017).