Question

an electrician charges $40 to come to your house. she also charges $55 for each hour that she works. the electrician charges you a total of 190$. how many hours does the rctrician work at your home? use h for the number of hours

Answer 1

she worked 2.72 hours

Explanation

Step 1

Let x represents the total hours she worked

then

an electrician charges $40 to come to your house,so

Fixed charge=40

and

she also charges $55 for each hour that she works,so

variable charge=55*number of hours

variable charge=55*x

variable charge=55x

Hence, the total cost is

$\begin{gathered} \text{total cost= fixed charge+variable charge} \\ \text{total cost=40+55x}\rightarrow equation \end{gathered}$

Step 2

now, solve for x, when total cost = 190

Let

total cost=190

replace

$\begin{gathered} \text{total cost=40+55x}\rightarrow equation \\ \text{190=40+55x} \\ \text{subtract 40 in both sides} \\ \text{190-40=40+55x-}40 \\ 150=55x \\ \text{divide both sides by 55} \\ \frac{150}{55}=\frac{55x}{55} \\ 2.72=x \end{gathered}$

Hence, she worked 2.72 hours.

I hope this helps you