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17.2 Making scale drawings

2 Mark leaves his tent and walks 12 km on a bearing of 045°.
He then walks 16 km on a bearing of 275°.
a Make a scale drawing of Mark’s walk.
Use a scale where 1 cm represents 2 km.
b How far must Mark now walk to return to his tent?
c On what bearing must Mark now walk to return to his tent?
3 Jun lives 8 km south of Yue.
Jun leaves home and walks 6 km to a lake.
She walks on a bearing of 070°.
Yue leaves home and walks to meet Jun at the lake.
How far, and on what bearing, must she walk?
4 A yacht is 70 km west of a speedboat. Make scale drawings to
The yacht sails on a bearing of 082°. work out the answers to
The speedboat travels on a bearing of 252°. questions 3, 4 and 5
Could the yacht and the speedboat collide? Explain your answer. You will need to choose
suitable scales.
5 A lighthouse is 85 km north of a port.
The captain of a ship knows he is on a bearing of 145° from the lighthouse.
He also knows he is on a bearing of 052° from the port.
a How far is the ship from the lighthouse?
b How far is the ship from the port?

6 A map has a scale of 1 : 50 000.
a On the map, a footpath is 9 cm long. What is the length, in kilometres, of the footpath in real life?
b In real life a road is 18 km long. What is the length, in centimetres, of the road on the map?

7 Alicia is participating in a charity sailing race on the Mar Menor. 8 AEROPUERTO DE
The map shows the route she takes. 786 MURCIA-SAN JAVIER
The map has a scale of 1 : 250 000. 9 Start/Finish
a What is the total distance that Alicia sails? 2 MAR
Alicia earns €56 for charity, for every kilometre she sails. Los Alcázares
b What is the total amount that Alicia raises for charity?
Menor
7 El Carmoli 104
8

Summary

You should now know that: You should be able to:
+ A bearing gives the direction of one object from + Use bearings to solve problems involving distance
another. It is an angle measured from north in a and direction.
clockwise direction. + Make and use scale drawings and interpret maps.
+ A bearing can have any value from 000° to 360°.
It must always be written with three figures.

17 Bearings and scale drawing 163