Answer:
For what amount of calling do the two plans cost the same? __300__ minutes
What is the cost when the two plans cost the same? $ __55__
Step-by-step explanation:
We have 2 plans, A and B. We must find an equation that relates the cost of the plan based on the number of minutes of calls.
For plan A we have:
Fixed cost of $ 16.
Variable cost of 0.13(m)
Where m represents the minutes of additional calls.
Then the equation for the cost [tex]C_A[/tex] is:
[tex]C_A = 0.13m + 16[/tex]
For plan B we have:
Fixed cost of $28.
Variable cost of 0.09(m)
Where m represents the minutes of additional calls.
Then the equation for the cost [tex]C_B[/tex] is:
[tex]C_B = 0.09m + 28[/tex]
To find out when the plans cost the same, we must equalize both equations and solve for m:
[tex]C_A = C_B\\\\0.13m + 16 = 0.09m + 28\\\\0.04m = 12\\\\m = 300\ minutes.[/tex]
When the number of additional minutes is 300 the costs of the plans are equal to:
[tex]C_A = C_B = 0.13(300) + 16\\\\C = \$\ 55[/tex]
