How many metres is 5 cm?
Scale drawings — Notes & Worked Examples Show / Hide
Explanation:
A scale drawing shows a real object reduced in size using a fixed ratio. A scale may be given with units (e.g. 1 cm represents 5 m) or as a unitless ratio (e.g. 1 : 500, which means 1 cm on the drawing = 500 cm in real life).
To find a real-life length, measure the drawing length in cm and multiply by the scale. To find a drawing length, divide the real-life length by the scale (converting to matching units first if needed).
Example 1: A map has a scale of 1 : 25,000. Two villages are 6 cm apart on the map. Find the real distance in km.
Example 2: A plan uses a scale of 2 cm to 5 m. A rectangular garden is 17.5 m long by 10 m wide. Find its length on the plan.
How many metres is 5 cm?
Two towns are 8cm apart on the map
Find the real distance in km
Worked Solution & Answer
8 km
The tree has drawn height 7 cm.
The student has drawn height 2.5 cm.
Work out the actual height of the student.
Worked Solution & Answer
Actual height of student = 2.5 × 0.6 = 1.5 m. A1
Scale: 1 cm represents 1.65 m
Give your answer in metres, to the nearest centimetre.
Worked Solution & Answer
Actual length of car = 13.23.8 ≈ 3.47368 m M1
To the nearest centimetre (2 d.p.): 3.47 metres A1
PQ = 4 cm QR = 6.5 cm
The actual distance PQ is 50 metres less than the actual distance QR.
Worked Solution & Answer
Difference in actual distance = 50 metres M1
2.5 cm = 50 m ⇒ 1 cm = 50 ÷ 2.5 = 20 m A1
Label each room.
Use a scale of 1 cm represents 2 feet
Worked Solution & Answer
Bathroom: 8 ft ÷ 2 = 4 cm, 6 ft ÷ 2 = 3 cm
Bedroom: 8 ft ÷ 2 = 4 cm, 10 ft ÷ 2 = 5 cm M1
Kitchen: 12 ft ÷ 2 = 6 cm, 8 ft ÷ 2 = 4 cm
Living room: 12 ft ÷ 2 = 6 cm, 14 ft ÷ 2 = 7 cm A1
The scale drawing shows the path on a centimetre grid.
Scale: 1 centimetre represents 10 metres
Worked Solution & Answer
Distance B to C = 3 cm = 30 m
Total distance along path = 40 + 30 = 70 m A1
The distance that he drives is 590 km.
This distance is greater than the actual straight line distance between Paris and Bordeaux.
How much greater?
Show your working clearly.
Worked Solution & Answer
Actual straight line distance = 6.2 × 80 = 496 km (or 480–512 km) M1
Difference = 590 − 496 = 94 km (or 78–110 km). A1
Mark point B on the centimetre grid.
Use a scale of 1 centimetre represents 100 metres.
20 (b) Points C and D are shown on a different centimetre grid.
Scale: 1 : 1000
Work out the bearing of D from C.
20 (c) Work out the actual distance, in metres, of D from C.
Use the scale 1 : 1000
Mark point B on the centimetre grid.
Use a scale of 1 centimetre represents 100 metres. [2 marks]
Scale: 1 : 1000
Work out the bearing of D from C. [1 mark]
Use the scale 1 : 1000 [1 mark]
Worked Solution & Answer
North-East is at bearing 045°. A1
Actual distance = 4 × 1000 cm = 4000 cm = 40 metres. B1
Work out the perimeter of the real tennis court.
Give your answer in metres.
Worked Solution & Answer
Real length = 11.5 × 200 = 2300 cm = 23 m M1
Real width = 5.8 × 200 = 1160 cm = 11.6 m M1
Perimeter = 2 × (23 + 11.6) = 69.2 m A1