The maths of MLMVL would be:
M=1000;
LM=1000-50=950;
VL=50-5=45;
total=1000+950+45=1995;
*but* the number would not exist in the first place and is presumably a misprint. The correct way of translating numbers into roman numerals is one digit at a time:
1000=M;
900=1000-100=CM;
90=100-10=XC;
5=V;
total=MCMXCV.
The need to do this one-digit-at-a-time method means that MVM is also wrong. it may be simpler to subtract 5 from 1000, but the standard way of doing roman numerals is to do it the log way (900+90+5).