Regarding decibels (dB): Say I have a 10w transmitter. A 3dB gain means a doubling of power, right? So I'd now have 20w output.?

But a 3 dB attenuation means I have a 5w output, right?

This seems awkward. With 3dB of gain, I gain 10 watts of power. With 3 dB attenuation, I only lose 5 watts. Is this correct? If not, can you explain?
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