Math 8 Unit 4 Review

The scatterplot shows the energy in watts and the light output per watt of several lightbulbs. Which statement best describes the association between the energy between the output of these lightbulbs?

• as the energy increases, the light output increases

• as the energy increases, the light output decreases

• as the energy increases, the light output remains the same

• there is no apparent association between the energy and light output

What is the x-coordinate of the ordered pair that best represents a solution to both equations?

Mathematical Equivalence

ON

Organize these options into the right categories

Groups:

(a) PROPORTIONAL

,

(b) NON-PROPORTIONAL

• Chris purchases pears at the grocery store for $3.49 per pound.

• Blake rented a canoe at a lake for $25 an hour plus $10 for his life jacket.

• Eric's tile cleaning service charges $75 for a service fee plus $30 per hour.

• Sara is paid $20 per hour for babysitting

Organize these options into the right categories

Groups:

(a) PROPORTINAL

,

(b) NON-PROPORTIONAL

• 
• 
• 
• 
• 

Organize these options into the right categories

Groups:

(a) PROPORTINAL

,

(b) NON-PROPORTIONAL

• 
• 
• 
• 

The distance a truck travels varies directly with the number of hours driven. A truck travels 268 miles in 4 hours. If the truck continues to travel at this same rate, how long will it take the truck to drive 938 miles?

Mathematical Equivalence

ON

The plot shows the average price of a ticket to a certain amusement park from 1997 to 2006.

Based upon the information, select the point on the graph to show the estimated cost in dollars for a ticket in 2009?

The choir recorded the number of cookies sold. Based on this scatterplot, which of the following do NOT represent a reasonable prediction for the total number of cookies sold in 3 hours? Select the THREE that apply.

• 90

• 105

• 110

• 120

• 135

The scatterplot shows the number of people in a household and the average amount of money spent on water. Complete the statement to best describe the relationship between the number of people in a household and the average amount spent on water. Choose the correct answer from each drop down menu to complete the statement.

As the x-values increase, the y-values ​ (a)  

This represents a ​ (b)   ​ (c)   association between the number of people in a household and the average amount spent on water.

• increase
• decrease
• positive
• negative
• linear
• non-linear

The graph models the value of a machine over a 10-year period. Which equation best represents the relationship between x, the age of the machine in years, and y, the value of the machine in dollars over this 10-year period?