M3.4.7 For the adult
Maps and scale drawings
On a map a road is 4 cm long. The scale is 1 : 50 000. How long is the real road?
What this chapter teaches
A scale such as 1 : 50 000 compares a length on the map with the same length on the ground, in the same unit. Change centimetres to metres or kilometres to read a real distance. Divide to go from the ground back to the map.
Three questions to ask
There is no one right wording. Listen for the idea.
- What does the scale 1 : 50 000 mean in words?
- Why do you divide by 100 and then by 1 000 to change centimetres to kilometres?
- How would you draw a room 5 m by 4 m with 1 cm for each 1 m?
After the chapter, the learner can
- Use a scale of 1 : 50 000 to find a real distance
- Draw a plan of a room with 1 cm for each 1 m
What they copy into their notebook
On a 1 : 50 000 map, 1 cm is 50 000 cm on the ground. That is 500 m. Multiply to go from map to ground. Divide to go back.