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Homework Help: Electrical Energy and Power (Wrong because of decimal place)

  1. Mar 2, 2007 #1
    1. The problem statement, all variables and given/known data
    How much does it cost to watch a complete 21-hour-long World Series on a 180-W television set? Assume that electricity costs $0.070/kWh

    3. The attempt at a solution

    [tex] \frac {0.070}{kWh} = \frac {x}{(180*10^{3}kW)(21h)}[/tex]

    [tex] \frac {0.070*(180*10^3 kW)(21h)}{kWh} = x [/tex]

    I got $264,600 when the answer is suppose to be 26 cents. What am I doing wrong here? Thanks.
  2. jcsd
  3. Mar 2, 2007 #2
    Why do you have 180*[tex]10^3[/tex]kW?
  4. Mar 2, 2007 #3
    Yes, you've converted your power the wrong way.
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