Question

Find the number of kilowatt-hours of energy used when a 110-watt light bulb burns for 215 hours.

Answer 1

We determine the kilowatt-hour by multiplying the energy in kilowatt and the time in hours. We do as follows:

kWh = 110 W ( 1 kW / 1000 W ) (215 hrs )
kWh = 23.65 kWh

Hope this answers the question. Have a nice day.