Chapter 3.2, Problem 12CFU

(a)

To determine

To Find: The graph for the function that describes the cost for $x$ hours of labour.

Explanation of Solution

Given:

The cost of the labour servicing the car at B and B automotive is $50 for each whole hour or for any fraction of an hour.

Calculation:

Consider the cost for $x$ hours is $y=50x$ then the

The graph for the function that describes the cost for $x$ hours of the labour is shown in Figure 1

  

Figure 1

(b)

To determine

To Find: Thegraph for the function that shows $25 extra charges when it is decided to change the oil and the fluid.

Answer to Problem 12CFU

The x intercept of the graph is 0 and 0.3.

Explanation of Solution

Consider that for every value of the hour or any fraction of the hour the value of $y=50x$ and the value of $x=1$ .

Consider for the additional charge the equation is $y=50x+25$ .

The required graph is shown in Figure 2.

  

Figure 2

(c)

To determine

To Find: The cost of servicing the car that is required 3.45 hours of labour when the owner requires to change the oil and the fluid checks.

Answer to Problem 12CFU

The required value of amount is $\$197.5$ .

Explanation of Solution

Consider the expression is,

  $y=50x+25$

Then for the labour of 3.45 hours he amount is,

  $\begin{array}{c}y=50\left(3.45\right)+25\\ =\$197.5\end{array}$