00:01
So we have a 16 watt light bulb and we're told that the energy costs in this particular event are 28 cents per kilowatt hour.
00:11
So we want to know what's the cost of running the 16 watt light bulb for five hours a day, presumably for an entire year.
00:20
So five hours a day times 365 days in a year tells us how many hours we're going to be using this.
00:31
So five times three hundred 365 is 1 ,825 hours and so to run this for one hour costs just 16 watt hours and so really or another way of writing that is 16 divided by 1 ,000 kilo watt hours it's the same thing so that's for one hour if we multiply this usage over so let's look at this if we multiply this usage 16 watt hours over the course of 1825 hours.
01:10
So basically 16 watts times 1825 hours.
01:15
We get 29 ,200 watt hours.
01:21
Now, we need to look at kilowatt hours, so we divide by 1 ,000 here.
01:25
So divide this by 1 ,000...