Chapter 2.5, Problem 91PE

(a)

To determine

The cost function to represent the cost, $C\left(x\right)$ , for $x$ training sessions for the given month of which the trainer cost include monthly costs of $\text{\$69}\text{.95}$ for phone services, and $\text{\$39}\text{.99}$ for his website and advertising. He pays a $\text{\$20}$ fee to the gym for each session in which he trains a client.

(b)

To determine

The average cost function to represent the average cost, $\overline{C}\left(x\right)$ , for $x$ training sessions for the given month of which the trainer cost include monthly costs of $\text{\$69}\text{.95}$ for phone services, and $\text{\$39}\text{.99}$ for his website and advertising. He pays a $\text{\$20}$ fee to the gym for each session in which he trains a client.

(c)

To determine

To calculate: The values of $\overline{C}\left(5\right),\overline{C}\left(30\right),\text{ and }\overline{C}\left(120\right)$ in the average cost function, $\overline{C}\left(x\right)=\frac{20x+109.94}{x}$ .

(d)

To determine

To calculate: The value of average cost approach, if the number of sessions were unlimited. Realistically, the trainer can have $120$ sessions per month.