An electric appliance requires 487 watts. How much would it cost to run the appliance for a total of 105 minutes at a cost of $0.19 per kilowatt hour?

1 Answer
Dwight
Dec 18, 2016

The cost of all that electricity will be #"$0.16"# (rounded to the nearest one cent).

Explanation:

Its best to do this by converting 105 minutes to 1.75 hours, and 487 watts to 0.487 kW. These are non-standard units for a Physics problem, but they fit the situation here nicely.

Now, all you have to do is multiply:

#"0.487 kW" xx "1.75 h" = "0.85225 kWh"#

At #"$0.19 per kWh"# this will come to #"$0.162"#

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