The effectiveness of furniture polish at keeping germs at bay.

Before: 70%

After:40%

Effectiveness = 30%

I have to pay $11.75 for using the PlayStation 3 for 2 hours a day for every day in a year. To find this I first found the wattage of a ps3 which is 70. The electricity cost is 23 cents/kwh. Running time per day is 2 hours. Per year is 2 x 365 so per year is 730 hours. 730 hrs x 70w equals 51,100. 51,100 divided by 1000 is 51.1 kwh. 51.1 x 23 cents equals 1,175 cents divided by 100 equals $11.75 per year.