Bearings and Scale Drawings: Cambridge KS3 Page 285 Question 2 | 方位角与比例绘图：剑桥KS3第285页第2题

📚 Bearings and Scale Drawings: Cambridge KS3 Page 285 Question 2 | 方位角与比例绘图：剑桥KS3第285页第2题

In this Cambridge KS3 Mathematics revision article, we focus on the skills behind page 285, question 2: reading bearings, using a scale drawing, and checking distance and direction results. The worked ideas below will help you answer this type of question accurately under test conditions.

在这篇剑桥KS3数学复习文章中，我们聚焦第285页第2题背后的技能：读取方位角、使用比例图，以及检验距离和方向结果。下面的解题思路将帮助你在考试条件下准确地回答这类问题。

1. What Page 285 Question 2 Tests | 第285页第2题考查什么

Question 2 on page 285 belongs to the bearings and scale drawing topic. It usually gives a point, a North line, and a second point placed at a measured angle and distance. You are expected to measure or calculate the bearing, apply the map scale, and possibly describe the return journey.

第285页第2题属于方位角与比例绘图主题。题目通常给出一个点、一条北方参考线，以及按一定角度和距离放置的另一个点。你需要测量或计算方位角、应用比例尺，并可能描述返程路线。

The question is not only about reading an angle: it tests whether you can combine angle measurement, three-figure bearings, and proportional reasoning from the scale.

这道题不仅仅是读取角度：它考查你能否将角度测量、三位数方位角和比例尺中的比例推理结合起来。

2. Key Rules for Bearings | 方位角的关键规则

Bearings are angles measured clockwise from the North direction. They are always written with three digits, so 70 degrees must be written as 070 degrees. A full circle covers bearings from 000 degrees to 360 degrees.

方位角是从正北方向顺时针测量的角度。它们总是写成三位数，所以70度必须写成070度。整个圆周对应的方位角范围是从000度到360度。

• North = 000° | 正北 = 000°
• East = 090° | 正东 = 090°
• South = 180° | 正南 = 180°
• West = 270° | 正西 = 270°

3. Using a Protractor Correctly | 正确使用量角器

Place the protractor centre exactly on the point you are measuring from. Align its 0-degree line with the North line drawn on the diagram. Read clockwise until the line joining the two points crosses the protractor scale.

将量角器的中心准确放在你正在测量的点上。把量角器的0度线与图上画出的北方参考线对齐。顺时针读取数值，直到连接两点的线穿过量角器刻度。

If the angle is less than 100 degrees, add a leading zero when writing the bearing. For example, 65° becomes 065°.

如果角度小于100度，书写方位角时要加上前导零。例如，65°应写成065°。

4. Understanding Scale Drawing Language | 理解比例图语言

A scale drawing uses a ratio such as 1 cm : 5 km. This means every 1 cm measured on the diagram represents 5 km in real life. You must read the scale carefully because different questions use different units.

比例图使用比如1 cm : 5 km这样的比。这表示图上测量到的每1厘米代表实际生活中的5千米。你必须仔细读取比例尺，因为不同题目可能使用不同的单位。

Common KS3 scales include 1 cm : 1 m, 1 cm : 10 km, and 1 : 50 000. In all cases, the diagram distance is multiplied or divided by the correct scale factor.

常见的KS3比例尺包括1 cm : 1 m、1 cm : 10 km和1 : 50 000。无论哪种情况，都需要将图上的距离乘以或除以正确的比例因子。

5. From Map Distance to Real Distance | 从地图距离到实际距离

If you know the distance on the diagram and the scale, the real distance is calculated by multiplication. Use the formula below.

如果你知道图上的距离和比例尺，实际距离可以通过乘法计算。使用下面的公式。

Real distance = Diagram distance × Scale factor

For example, if a boat is 4 cm from a harbour on a map with scale 1 cm : 3 km, the real distance is 4 × 3 = 12 km.

例如，如果一艘船在地图上距离港口4厘米，比例尺为1 cm : 3 km，那么实际距离就是4 × 3 = 12千米。

6. From Real Distance to Diagram Distance | 从实际距离到图上距离

Sometimes the question gives the real distance and asks how far apart the points should be on the scale drawing. In this case, divide the real distance by the scale factor.

有时题目给出实际距离，询问在比例图上这些点应该相距多远。这时，需要将实际距离除以比例因子。

Diagram distance = Real distance ÷ Scale factorPublished by TutorHao | KS3 Mathematics Revision Series | aleveler.com

更多咨询请联系16621398022（同微信）