Scale Drawings

Pre-GCSE Maths

Aims and ObjectivesAims

To be able to accurately measure a scale drawing and to calculate real life sizes. (AoN portfolio)

ObjectivesTo take measurements from scale drawingsTo calculate real life sizesTo find the area of a room and a patioTo calculate distances on a map

Which is the biggest in real life?

What scale has been used?

To be able to compare them properly we would need to know the scale that they had been drawn to.

This would be written as 1:50, 1:100, etc.

1:50 means that whatever is on paper is 50 times bigger in real life.

1:100 means that whatever is on paper is 100 times bigger in real life.

Here is that information.

1:50 1:25 1:30

Let’s calculate his real height.

If this man was drawn to a scale of 1:50 his height would be what in real life?

4cm x 50 = 200cm 4cm 200cm =

2m

Scale 1:50

Let’s calculate his real height.

If this man was drawn to a scale of 1:25 his height would be what in real life?

8cm x 25 = 200cm 200cm = 2m 8cm

Scale 1:25

Let’s calculate his real height.

If this man was drawn to a scale of 1:30 his height would be what in real life?

6cm x 30 = 180cm 180cm = 1.8m 6 6cm

He is the shortest person. Scale 1:30

No room for error.

There is no guessing with scale drawings.

If the scale drawing has been drawn accurately, we will always be able to calculate the real life size of the object drawn.

We must always know the scale that has been used.

Demonstration

Click here to see how scale drawings actually work.

Student Activities

Complete tableMeasure items drawn to scale

Measure areas off plan

Map Activity

Maps are usually drawn to a very small scale, i.e. 50,000 or 100,000 times smaller than in real life.

We can accurately measure distances by taking measurements off the map and multiplying them by the scale shown.

Students to complete “As the crow flies” activity

Extended activities as necessary

Aims and Objectives

AimsTo be able to accurately measure a scale drawing and to calculate real life sizes.

ObjectivesTo take measurements from scale drawingsTo calculate real life sizesTo find the area of a room and a patioTo calculate distances on a map