QUESTION A
To find the cost of making 300 minutes of calls, we can trace the graph from where the x-axis is 300 to the graph and then get the value on the y-axis. This is shown below:
Therefore, the cost of the plans are:
[tex]\begin{gathered} Plan\text{ }A=24 \\ Plan\text{ }B=20 \end{gathered}[/tex]
Therefore, PLAN B costs less.
The difference between the two plans will be:
[tex]\Rightarrow24-20=4[/tex]
Therefore, Plan B costs $4 less than Plan A.
QUESTION B
Both plans cost the same at the point where the two graphs intercept. Checking the graph, this occurs when:
[tex]x=250[/tex]
Therefore, the number of minutes that both plans cost the same is 250 MINUTES.
Plan B has a constant price of $20, regardless of the number of minutes used. However, Plan A is variable. The cost of Plan A only exceeds $20 after 250 minutes.
Therefore, before this time, PLAN B costs more.
