Understanding Ratios and Proportionality

This video tutorial introduces proportional relationships using tables, focusing on concepts like constant proportionality and unit rates. It provides practical examples, such as recipes, to illustrate these concepts. The video also includes homework problems to reinforce learning and concludes with a summary of key concepts.

What is a constant proportionality?

• A number that is always zero

• A variable that changes with time

• A random number chosen for calculations

• A fixed number that relates two variables in a proportional relationship

If 2 cups of rice serve 6 people, how many people can be served with 10 cups of rice?

• 30 people

• 20 people

• 15 people

• 25 people

What is the unit rate if 6 spring rolls serve 3 people?

• 3 spring rolls per person

• 0.5 spring rolls per person

• 2 spring rolls per person

• 1 spring roll per person

How do you find the reciprocal of a constant proportionality?

• Multiply the constant by 2

• Divide the constant by itself

• Add 1 to the constant

• Flip the numerator and denominator

What is the constant proportionality if 8 tablespoons of honey are used for 10 cups of flour?

• 10/8

• 8/10

• 5/4

• 4/5

In a proportional relationship, what does the constant proportionality represent?

• The sum of the variables

• The difference between the variables

• The product of the variables

• The ratio of the dependent variable to the independent variable

If a map scale is 1 inch to 30 miles, what is the actual area of a park represented by a 6x4 inch map?

• 21,600 square miles

• 900 square miles

• 1,800 square miles

• 720 square miles

What is the scale factor if a map needs to be reduced to fit a brochure with an area of 6 square inches?

• 3

• 2

• 1/2

• 1/3

How many dimes are equivalent to 4 quarters?

• 8 dimes

• 10 dimes

• 15 dimes

• 20 dimes

Which of the following ratios is equivalent to 4:7?

• 10:14

• 20:35

• 16:28

• 8:15