I have just read through the Lognormal section of the Quantative Methods Study Session. While I get the concept generally (it is the disribution of the original distribution raised to e and can reflect periodic investment return ratios), I am totally confused as to some of the equations and applications (e.g., the variance calculation makes little sense to me).

Question is this: How much of this do I need to know? Do I need to be able to make these calculations for the test or just to kind of know the concept from a 30,000 ft level?

Thanks. (BTW, the question is general one and not specific to anything that has been on a previous test.)