ANSWER:
(a) $29.99
(b) $37.49
(c) $30.24
STEP-BY-STEP EXPLANATION:
We have a function by part to calculate the monthly cost of a cell phone plan.
If the consumption is between 0 and 300 minutes, the value will always be $29.99. While if the consumption is greater than 300 minutes, the value is given by the following equation:
[tex]C\mleft(x\mright)=0.25x-45.01[/tex]
Knowing the above, we calculate in each case:
(a) 190 minutes.
It is in the interval between 0 and 300 minutes, therefore, the cost is $29.99.
C (190) = $29.99
(b)
[tex]\begin{gathered} C(330)=0.25\cdot330-45.01 \\ C(330)=82.5-45.01 \\ C(330)=37.49 \end{gathered}[/tex]
(c)
[tex]\begin{gathered} C(301)=0.25\cdot301-45.01 \\ C(301)=75.25-45.01 \\ C(301)=30.24 \end{gathered}[/tex]
