Question

The Chan’s electric bill for September was $40.70 which included a tax of $1.98. If the Chan’s used 320 kilowatts per hour of electricity that month, find the cost per kilowatt-hour.

Answer 1

Take off the tax: 40.70-1.98=$38.72. So 320kWh (it couldn’t be kW/h, because that would be astronomical over a month!) cost $38.72 and 1kWh=$38.72/320=$0.121 or about 12c per kWh.