Ron H in post #16 explained it.to be honest, i cannot quite figure out where my calculations have gone wrong. but a gain of 8 sounds more correct.
When the frequency is equal to the resonance frequency of the L/C circuit, the L/C combination may be replaced by a short. You can then see that the 1.2k resistor is simply an additional load from the input to ground. Since the source is assumed to be a zero output impedance device, the 1.2k load does nothing when it's connected directly to the source, as it is when the L/C circuit is at resonance.
Off resonance, the impedance of the L/C circuit combined with the 1.2k forms a voltage divider.
So, at resonance, the 1.2k does nothing. Off resonance, it has an effect.