BR100 Feedback Resistor / Rf1 and Rf2 not equal?

[Hybrid fourdoor]

Looking at the diagram at National for the BR100 (Bridged) It says Rf1/Ri1 is 47K/4.7K, but Rf2/Ri2 is 51.1K/4.7K. Everything else in the schematic is mirrored, and even in the parrellel schematic each IC is perfectly mirrored. Is this a misprint or is it supposed to be offset like that for a reason?

Thanks,
David

 

[peranders]

This is right!

Gain for inverting amp Rf/Ri

Non-inverting Rf/Ri +1

Note this +1!

Non-inverting amps can't have lower gain than 1, law of nature.