http://www.ck12.org Chapter 7. Organizing and Displaying Data
From the graph, the base fee that is charged for each plan is obvious. These values are found on they-axis. Plan
A charges a base fee of $200.00, Plan C charges a base fee of $100.00, and Plan B charges a base fee of $50.00.
The cost per hour can be calculated by using the values of the intersection points and the base fee in the equation
y=mx+band solving form. Plan B is the best plan to choose if the lawn maintenance takes less than 12.5 hours.
At 12.5 hours, Plan B and Plan C both cost $150.00 for lawn maintenance. After 12.5 hours, Plan C is the best
deal, until 50 hours of lawn maintenance is needed. At 50 hours, Plan A and Plan C both cost $300.00 for lawn
maintenance. For more than 50 hours of lawn maintenance, Plan A is the best plan. All of the above information
was obvious from the graph and would enhance the decision-making process for any interested client.
Guided Practice
The local arena is trying to attract as many participants as possible to attend the community’s “Skate for Scoliosis”
event. Participants pay a fee of $10.00 for registering, and, in addition, the arena will donate $3.00 for each hour a
participant skates, up to a maximum of 6 hours. Create a table of values and draw a graph to represent a participant
who skates for the entire 6 hours. How much money can a participant raise for the community if he/she skates for
the maximum length of time?
Answer:
The equation for this scenario isy= 3 x+10, whereyrepresents the money made by the participant, andxrepresents
the number of hours the participant skates.
TABLE7.4:
Numbers of Hours Skating Money Earned
0 $10.00
1 $13.00
2 $16.00
3 $19.00
4 $22.00
5 $25.00
6 $28.00The dependent variable is the money made, and the independent variable is the number of hours the participant