What a coincidence, I should have done it earlier today. Skilled counterparts end up converting factors based on the unit you give him, but as part of it LengthConverter.
LengthConverter lc = new LengthConverter();
string qualifiedDouble = "10pt";
double converted = lc.ConvertFrom( qualifiedDouble );
Alternative
double original = 10.0;
double converted = original * 1.333333333;
This, for example, converts "10pt" to 13.3333333. You can also use the conversion factors that the article provides, but I prefer to use the above, as factors are built into the class.
Edited: In response to a comment about the lines ...
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