2. introduction to scales

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SCALE
Why do we need a scale?
• A map maker puts important information
about a large piece of land on to a small of
piece of paper.
• The SCALE of a map is the length used on the
map to represent a certain distance on the
ground.
Why is scale important?
• The map maker basically “shrinks” everything
on the land to fit onto the paper.
• If the map maker didn’t shrink to scale,
everything would be skewed.
• Scale is important because it keeps everything
at the same ratio.
Why do we need a scale?
• A map maker puts important information
about a large piece of land on to a small of
piece of paper.
• The SCALE of a map is the length used on the
map to represent a certain distance on the
ground.
Now that you
know why we
NEED SCALES...
Scales can be
expressed in
3 WAYS:
LINE SCALE:
• A line drawn on a map that represents
distances on the ground.
WRITTEN SCALE:
• A scale represented by a written phrase.
RATIO SCALE:
• When given a ratio scale of 1:100 000,
it means that 1 cm on the map
represents 100 000 cm in real life.
How do I Convert?
CM → KM
• Divide by 100,000
• Move the decimal 5 places to the left
KM → CM
• Multiply by 100,000
• Move the decimal 5 places to the right
Scale Conversion Practice:
CM to KM
Move decimal 5 left
←
KM to CM
Move decimal 5 right
→
Written Scale
Ratio Scale
1 cm = 1km
1: 100 000
1 cm = 250km
1: 25,000,000
1 cm = 0.5 km
1: 50 000
1 cm =11.25 km 1: 1,125,000
Measure line length
X both sides by length
(i.e. 8 cm)
Line Scale
0
2
0
0
0km
4
6
1,000
1
2
30
8 km
2,000km
3
60
4km
90
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