What is the fuel capacity difference between the John Deere 9RX 640 and 9RX 710?

The John Deere 9RX 640 has a fuel capacity of 400 gal. and the John Deere 9RX 710 has a fuel capacity of 515 gal., a difference of 115 gal. The John Deere 9RX 710 has the higher fuel capacity.