Unit 2, Lesson 7
Units in Scale Drawings
Accelerated 7
7.1
Warm-up
A map of a park says its scale is 1 to 100.
- What do you think that means?
- Give an example of how this scale could tell us about measurements in the park.
7.2
Activity
Your teacher will give you a scale drawing of the Apollo Lunar Module. It is drawn at a scale of 1 to 50.
- Estimate the actual length of one leg of the spacecraft to the nearest 10 centimeters. Explain or show your reasoning.
- Estimate the actual height of the spacecraft to the nearest meter. Explain or show your reasoning.
- Neil Armstrong was 71 inches tall when he went to the Moon. How tall would he be in this scale drawing? Show your reasoning.
- Sketch a stick figure to represent yourself standing next to the Apollo Lunar Module. Make sure the height of your stick figure is to scale. Show how you determined your height on the drawing.
7.3
Activity
As of 2016, Tunisia holds the world record for the largest version of a national flag. It was almost as long as four soccer fields. The flag has a circle in the center, a crescent moon inside the circle, and a star inside the crescent moon.
- Complete the table. Explain or show your reasoning.
flag length flag height height of
crescent moonactual 396 m 99 m at 1 to 2,000 scale 13.2 cm -
Complete each scale with the value that makes it equivalent to the scale of 1 to 2,000. Explain or show your reasoning.
- 1 cm to ____________ cm
- 1 cm to ____________ m
- 1 cm to ____________ km
- 2 m to _____________ m
- 5 cm to ___________ m
- ____________ cm to 1,000 m
- ____________ mm to 20 m
-
- What is the area of the large flag?
- What is the area of the smaller flag?
- The area of the large flag is how many times the area of the smaller flag?
Student Lesson Summary
Sometimes scales come with units, and sometimes they don’t. For example, a map of Nebraska may have a scale of 1 mm to 1 km. This means that each millimeter of distance on the map represents 1 kilometer of distance in Nebraska. Notice that there are 1,000 millimeters in 1 meter and 1,000 meters in 1 kilometer. This means there are or 1,000,000 millimeters in 1 kilometer. So, the same scale without units is 1 to 1,000,000, which means that each unit of distance on the map represents 1,000,000 units of distance in Nebraska. This is true for any choice of unit to express the scale of this map.
Here is some information about equal lengths that you may find useful.
Customary Units
1 foot (ft) = 12 inches (in)
1 yard (yd) = 36 inches
1 yard = 3 feet
1 mile = 5,280 feet
Metric Units
1 centimeter (cm) = 10 millimeters (mm)
1 meter (m) = 1,000 millimeters (mm)
1 meter = 100 centimeters
1 kilometer (km) = 1,000 meters
Equal Lengths in Different Systems
1 inch = 2.54 centimeters
1 foot 0.30 meter
1 mile 1.61 kilometers
1 centimeter 0.39 inch
1 meter 39.37 inches
1 kilometer 0.62 mile
None