Inquisitor 1183

[RossR]

I've solved all of this, but 6D is bugging me. There is only one possible answer that fits and agrees with the definition but I cannot see how the clue takes us there. Could somebody please explain it:

Mathematician, one whining, gets 250 rather than 400 (5)

[dr b]

PULER (One whining), substitute E (250) for P (400) --> EULER.

[Lie-in King]

Rats! I was trying to lose CD from Euclid & had forgotten the medieval letters...

[RossR]

Thanks very much Dr B. I knew there were more symbols than the few used for Roman numerals but I couldn't find them anywhere.

[dr b]

look here under the "middle ages" subheading:

http://en.wikipedia.org/wiki/Roman_numerals

[RossR]

Thanks again!