Scale Factor
What is a Scale Factor?
The number or ratio that you change by to create a copied shape or image.
What is 1/5 as a Percent?
20%
A radius is half the length of a diameter
The price of a bag of trululus is 12mil. Write an equation to represent this.
Use c for cost and b for bag pof trululus
C = 12b
Where is your math teacher from?
answers will vary
A photograph of a beetle is enlarged to create a poster. The actual beetle is 3 cm long, and the length of the beetle on the poster is 15 cm. What is the scale factor of the enlargement?
5
What is 23% of 18?
4.14
A circle has a radius of 7. What is the circumference?
14pi or 43.96
What is a constant of proportionality?
The rate at which we are changing by. A constant rate of change.
Which scale factor will cause a shape to shrink? Select all that apply.
4
â…“
0.8
1
2 and 3
A scale factor was applied to a shape to create a scale copy. Choose all that are true.
The angles will stay the same
The side lengths will stretch or shrink
The shape will change
The shape will disappear
1 and 2
A runner had a goal of running 25 km. They ran 18 km, what percent of their goal did they run?
72%
A circle has a diameter of 18, what is its area?
81pi or 254.34
A cake recipe calls for 20g of sugar for every 2 ounces of cake batter. If you use 14 ounces of cake batter how many gra,ms of sugar will you need?
140g of sugar
How many people live in Medellin?
Around 4 million
What would be the area of a triangle with a height of 5 and a base of 3 if a scale factor of 4 was applied to it?
120
A shirt was on sale for 25% off. If it costs 64mil originally, how much does it cost after the discount?
48 mil
What is the difference between circumference and area of a circle?
The circumference is like the perimeter. It is the length around the circle. The area is the amount of space across the whole circle.
Create an equation to represent how many shoes there are in this room.
Use s for shoes and p for people
S=2p
A circular pond has a radius of 3.5 meters. How much fencing is needed to go around the entire pond?
7pi or 21.98
The floor of a classroom had a height of 20 and a length of 16. A student drew the floor in a scale drawing with a scale factor of 1/4. What is the area of the floor in the scaled drawing?
20
Write an equation to represent the cost (c) of a shirt (s) after a discount of 18% off.
C= 0.82s or C= s-0.18s
A circle has a circumference of 31.4, what is the area?
25pi or 78.5
What makes a graph proportional? Why?
A graph must go through the origin, and it has to be straight line to show that it has a constant rate of change.
What are the 3 biggest cities in Colombia?
Bogota, Medellin, Cali