Question

an electric utility company determines the monthly bill by charging 81 cents per kilowatt - hour (kwh) used plus a base charge of $22.55 per month. thus, the monthly charge is given by the function $f(w)=0.81w + 22.55$ dollars, where w is the number of kilowatt - hours. find $f(500)$ and explain what it means.
\bigcirc $f(427.55)=500$, this means that the monthly charge for 500 kilowatt - hours is $427.55$
\bigcirc $f(500)=427.55$, this means that the monthly charge for 427.55 kilowatt - hours is $500$
\bigcirc $f(500)=427.55$, this means that the monthly charge for 500 kilowatt - hours is $427.55$
\bigcirc $f(427.55)=500$, this means that the monthly charge for 427.55 kilowatt - hours is $500$

Explanation:

Step1: Substitute W=500 into function

$f(500) = 0.81\times500 + 22.55$

Step2: Calculate usage charge

$0.81\times500 = 405$

Step3: Add base charge to total

$405 + 22.55 = 427.55$

Step4: Interpret the result

$f(W)$ is monthly cost for $W$ kWh.

Answer:

$f(500) = 427.55$, this means that the monthly charge for 500 kilowatt-hours is $\$427.55$