Name: __________________________________
Proportions – (Lesson 5.2)

A ______________________ is an equation stating the two ratios (fractions) are equivalent. Two
quantities that form a proportion are ________________________________.
Determining Whether Ratios Form a Proportions:
Tell whether the following form a proportion.
4 8
=
5 9
20 4
=
25 5
3 15
=
5 25
Identifying Proportional Relationships:
You swim your first 4 laps in 2.4 minutes. You complete 16 laps in 12 minutes. Is the number of laps
proportional to your time?
Writing/Solve Proportions-(Lesson 5.3 & 5.4)
Writing a Proportion:
Example 1: Use the table to write a proportion.
Points
Game 1
12
Game 2
18
Shots
14
w
Example 2: Write a proportion to find how many points a student needs to score on the test to get the
given score.
The test is worth 50 points; test score of 40%
Solving Proportions Using Mental Math:
Example 3:
Solve
3 x
=
2 8
Step 1: Think: The product of 2 and
what number is 8?
Step 2: Because the product of 2 and 4 is 8,
multiply the denominator by 4 to find x.
3
x
=
2
8
3
x
=
2 8
2x?=8
The solution is x = ________.
Solving Proportions Using Cross Multiplication: (Preferred Way)
Example 4: Solve each proportion.
a.)
x 7
=
8 10
b.)
9
3
=
y 17
Real-Life Application:
Example 5:
Forty-eight pens are packaged in 4 boxes. How many pens are packaged in 9 boxes?
Example 6:
A person who weighs 120 pounds on Earth weighs 20 pounds on the Moon. How much does a
93 pound person weigh on the Moon?