The question is below:

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> Your raw sensor signal is 6.5 mV, and you are using an instrumentation amplifier to process it. The amplifier has a CMRR of 80 dB and a differential mode gain of 40 dB. If the RF noise on the leads from the thermocouple sensor to the data logger is 79 mV, what will the noise level be on the amplified signal in mV? (Type in a two-decimal number.)
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I tried the following steps:

1. Find common-mode gain from CMRR = 20log(Ad/Acm)
2. Multiply 79 mV with Acm to find the noise at the output

But it turns out that I was wrong. I would appreciate if anyone could help me with this.