Unit 4 Proportional Relationships and Percentages (Family Materials)
Here are the video lesson summaries for this unit. Each video highlights key concepts and vocabulary that students learn across one or more lessons in the unit. The content of these video lesson summaries is based on the written Lesson Summaries found at the end of lessons in the curriculum. The goal of these videos is to support students in reviewing and checking their understanding of important concepts and vocabulary. Here are some possible ways families can use these videos:
Keep informed on concepts and vocabulary students are learning about in class.
Watch with their student and pause at key points to predict what comes next or think up other examples of vocabulary terms (the bolded words).
Consider following the Connecting to Other Units links to review the math concepts that led up to this unit or to preview where the concepts in this unit lead to in future units.
Video Lesson Summaries
Section A Proportional Relationships with Fractions
This week your student is learning about proportional relationships that involve fractions and decimals. For example, a baker decides to start using
amount of sugar in the recipe ( |
amount of sugar the baker uses ( |
---|---|
1 cup |
|
2 cups |
The amount of sugar the baker actually uses,
Another way to write this equation is
Here is a task to try with your student:
The baker also decides to start using
How much of each ingredient will the baker use if the recipe calls for:
cups of milk? 3 tablespoons of oil?
What is the constant of proportionality for the relationship between the amount of liquid called for in the recipe and the amount this baker uses?
Solution:
-
cups. tablespoons.
, or equivalent.
Section B Percent Increase and Decrease
This week, your student is learning to describe increases and decreases as a percentage of the starting amount. For example, two different school clubs can gain the same number of students, but have different percent increases.
The cooking club had 50 students. Then they gained 6 students.
This is a 12% increase, because
They now have 56 students, which is 112% of the starting amount.
The computer club had 8 students. Then they gained 6 students.
This is a 75% increase, because
They now have 14 students, which is 175% of the starting amount.
Here is a task to try with your student:
The photography club had 20 students. Then the number of students increased by 35%. How many students are in the photography club now?
Solution:
27 students. Possible strategies:
The club gained 7 new students, because
. The club now has 27 students, because . The club now has 135% as many students as they started with, because
. That means they have 27 students, because .
Section C Applying Percentages
This week, your student is learning about real-world situations that use percent increase and percent decrease, such as tax, interest, mark-up, and discounts.
For example, the price tag on a jacket says $24. The customer must also pay a sales tax equal to 7.5% of the price. What is the total cost of the jacket, including tax?
The customer will pay 107.5% of the price listed on the tag, which is $25.80.
We can also find the percentage. For example, a backpack originally cost $22.50, but is on sale for $18.99. The discount is what percentage of the original price?
The sale price is 84.4% of the original price. The discount is
Here is a task to try with your student:
A restaurant bill is $18.75. If you paid $22, what percentage tip did you leave for the server?
Solution: