Vocabulary
What is the term for a drawing that represents an object at a smaller or larger size than its actual size?
Scale Drawing
True or False: A scaled copy of a square will always be a square.
True
A drawing has side lengths of 4cm, 6cm, and 8cm. The original object has side lengths of 8cm, 12cm, and 16cm. Are they scaled copies?
If yes, what is the scale factor?
Yes, the scale factor is 2.
On a blueprint, 1 cm represents 2m. A wall is 6 cm on the blueprint. How long is the real wall?
12 meters
You want to draw your bedroom on paper with a scale of 1m to 2cm. If your bed is 2m long, how long should it be on your drawing?
4cm
What is the term for the ratio of the size of the drawing to the size of the actual object?
Scale
If two shapes are scaled copies of each other, what is the relationship between their corresponding angles?
The corresponding angles are equal.
A triangle has angles of 30 degrees, 60 degrees, and 90 degrees. A second triangle has angles of 30 degrees, 60 degrees, and 90 degrees. Are they scaled copies of each other?
Yes, the angles are the same.
A model car is built at a scale of 1 to 20. If the model car is 8 inches long, how long is the real car?
160 inches (13 ft, 4 in)
A rectangular garden is 25m by 10m. You use a scale of 1cm to 5m. What will the garden's dimensions be on your drawing?
5cm by 2cm
What do we call a drawing that maintains the same shape but is a different size compared to the original object?
Scaled Copy
What happens to the perimeter of a shape if it is made a scaled copy with a scale factor of 2?
The perimeter doubles (or is multiplied by 2).
A rectangle has dimensions 5cm by 10cm, and a second rectangle has dimensions 6cm by 14cm. Are these scaled copies?
If yes, what is the scale factor?
No, the sides are not multiplied by the same number.
A map uses the scale 3cm to 4km.
(a) How many kilometers are represented by 12cm on the map?
(b) How many centimeters represent 10km?
(a) 16km
(b) 7.5km
A playground is a rectangle 12m long and 8m wide. Draw it using a scale of 1:100. Be sure to label your dimensions!
Drawing is 12cm long and 8cm wide.
What is the term for the number that represents how many times larger or smaller a scale drawing is compared to the original object?
Scale Factor
If two triangles are scaled copies, what is true about their corresponding sides?
They are multiplied by the same scale factor (or they have the same ratio).
A rectangle has dimensions of 5cm and 9cm. A second rectangle has dimensions of 2.5cm and 4.5cm. Are these scaled copies?
If yes, what is the scale factor?
Yes, the scale factor is 1/2.
On one map, 1cm represents 8km. A river is 32cm long. On another map, 1cm represents 2km. How long is the river on the second map?
128 centimeters
A door is 0.9m wide and 2.1m tall in real life. Make a scale drawing using the scale 1 to 30. Label your dimensions.
Drawing should be 3cm wide and 7cm tall.
What is the term used for the matching parts of two similar figures, such as matching angles or sides?
Corresponding Parts
True or False: The area of a scaled copy increases by the scale factor.
False.
A rectangle has dimensions 8cm by 12cm. A second rectangle has dimensions 10cm by 15cm. Are they scaled copies?
If yes, what is the scale factor?
Yes, the scale factor is 1.25.
A map has a scale of 3/4 inch to 6 miles.
(a) How many miles does 2 1/4 inches represent?
(b) How many inches represent 12 miles?
(b) 1 1/2 inches
A rectangular swimming pool is 25m by 15m. You want to draw it on paper with a scale of 1 to 50.
(a) What are the dimensions of the pool in the drawing?
(b) If the diving board is 2.5m long, how long should it be on the drawing?
(a) 50cm by 30cm
(b) 5cm