Question

An 80-watt coffee maker is used an average of 0.5 hours a day. Find the cost of using the coffee maker for two weeks at a cost of $0.08 per kilowatt-hour. $0.04 $44.80 $0.18 $0.06

Answer 1

80 W divided by 1000 (to convert to kW) = 0.08 kW
The total cost can be calculated by multiplying wattage by time by electricity cost. Note how the units will cancel out, given that 2 weeks is equal to 14 days.
(0.08 kW)(0.5 h/day)(14 days) = 0.56 kWh
Multiply by the cost: ($0.08/kWh)(0.56 kWh) = $0.0448

So the closest answer is the first choice.