Hi Shirley
I have had my share of Spanish speeding fines and I have always been told by the Guardia that have stopped me that the calculation is thus:
Speed Limit plus 10% for possible camera/radar error on the A7 that would be 132kph anything above that atracts a fine of €10 per kph above the 132 which means €10 for him and with a discount of 50% €5.
If it is more than that ask your insurance company to challenge the fine, it is a general inclusion in Spanish Insurance policies that they will contest traffic offences if you deem them unfair.
If he was caught on the Polaris World motorway the fine should be €230 minus 50% discount as the speed limit on that road is 100kph.