A 60 W light bulb at 120 V is left on in your house to prevent burglary, and the power charges 10 cents per kilowatt-hour, how much will it cost to leave the bulb on for 30 days?

Answer 1

(60 W•24hours •30 days)/1000=43.2 kW•h
43.2•0.1$=4.32$