Question

How much is the bill for a person who uses 800 kWh in a month ?

Answer 1

For a person who uses 800kwh. x = 800 , Since x is greater than 200 we will use

$\begin{gathered} 0.15(x-200)+20 \\ 0.15x-30+20 \\ 0.15(800)-10 \\ 120-10=110 \end{gathered}$