Question

mr. crawford hired an electrician to work at his house. the electrician charges $75 for the service call and $55 for every hour of work. the charges can be expressed by the function below, where $t$ represents the number of hours worked. $f(t)=75 + 55t$. if the total bill of the electricians service is $405, how many hours did he work? a 55 b 25 c 12 d 6 e 3

Explanation:

Step1: Set up the equation

We know that $f(t)=405$ and $f(t)=75 + 55t$, so we set up the equation $405=75+55t$.

Step2: Isolate the term with $t$

Subtract 75 from both sides of the equation: $405 - 75=75+55t - 75$, which simplifies to $330 = 55t$.

Step3: Solve for $t$

Divide both sides of the equation by 55: $\frac{330}{55}=\frac{55t}{55}$, so $t = 6$.

Answer:

D. 6