Decide between two new stereo amplifiers

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Homework Statement



You are trying to decide between two new stereo amplifiers. One is rated at 130 W per channel and the other is rated at 200 W per channel.
In terms of dB, how much louder will the more powerful amplifier be when both are producing sound at their maximum levels?


Homework Equations



dB = 10 log (I/Io)



The Attempt at a Solution



I was not sure If i can use the 130 W and 200 W as intensities...
 
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Power is proportional to the intensity so yes.
 


so the solution is :

dB = 10 log (130/200) ?
 
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