Proportional Relationships Practice Test Review

Proportional Relationships Practice Test Review

8th Grade Practice Test Review and More Problems to Solve

Find the Constant of Proportionality

Remember: a constant is a number

A blue whale travels 27.2 miles in 2 hours. What is the whale's average speed in miles per hour?

• Constant = y/x

• Constant = 27.2 / 2

• 13.6 miles per hour

Fill in the Blank

An orca whale travels 25.74 km in 2 hours. What is the whale's average speed in km per hour?

Is there a proportional relationship between miles and dollars? 

• Find the constant (y/x) for each row and compare:

• Row 1: constant =22.40/5 = 4.48

• Row 2: constant = 59.20/15 = 3.9466

• Row 3: constant = 77.60/20 = 3.88

• No, there is not a proportional relationship because...

Multiple Choice

Is there a proportional relationship between the number of trees and the number of apples?

• Yes

• No

Open Ended

Explain, using numerical evidence, why the chart DOES represent a proportional relationship.

Write a Proportional Line

Use the format y=kx

Which mathematical statement below represents a proportional relationship?

• Proportional Relationships are written in the form y=kx

Multiple Choice

Is the equation proportional? y=3x

• Proportional

• NOT Proportional

Multiple Choice

Is the equation proportional? y=3x +7

• Proportional

• NOT Proportional

Multiple Choice

Is the equation proportional? y=0.5x

• Proportional

• NOT Proportional

Multiple Choice

Is the equation proportional? y=x/5

• Proportional

• NOT Proportional

Given a constant we can write an equation.

• If the constant is 4, the equation of the line is y=4x

• If the constant is 9, the equation of the line is y=9x

• If the constant is 0.3, the equation of the line is y=0.3x

Fill in the Blank

If the constant is 15, what is the equation of the line in y=kx format

Fill in the Blank

If the constant is 7, what is the equation of the line in y=kx format

Fill in the Blank

If the constant is 0.5, what is the equation of the line in y=kx format

A company donates $200 for every home run hit in a local Baseball game. Write an equation for the situation, where y is the total amount of money donated and x is the number of home runs hit. 

• The constant is 200.

• We use the form y=mx to represent a proportional equation

• y=200x

Fill in the Blank

A company donates $25 for every pair of glasses collected during a school fundraiser. Write an equation for the situation, where y is the total amount of money donated and x is the number of glasses collected.

Type an equation to model the proportional relationship shown in the graph.

• y=mx

• Find the constant (unit rate) and substitute the value in for m. constant=y/x constant=38/2

• y=19x

Fill in the Blank

Type an equation to represent the proportional relationship shown in the graph. (You can use the point (2,100) to help you find the constant)

The table shown represents a proportional relationship. What is the constant of proportionality? 

• Remember a constant is a number.

• Constant = y/x constant = 132/8 = 16.5

• Constant =y/x constant =148.5/9 = 16.5

• The constant is 16.5

Fill in the Blank

What is the constant of proportionality shown in the table?

Application

Which store charges more for a sheet of stickers?

• The equation y=2.09x models the cost y of x sheets of stickers at Sally's Stickers . So, the constant is 2.09

• The table shows the relationship between the cost and the number of sheets of stickers at Henry's Stickers. The constant is y/x, so the constant is 6.15/3, 2.05

• Sally's Stickers charges more.

• 
  

Multiple Choice

What store charges more for bananas? Price Chopper's prices are listed in the table, Hannaford's is represented by the equation y=2.5x

• Price Chopper

• Hannaford

Make sure to study for the test tomorrow!