The Nun and the Integer

At our school, a students 2nd semester grade is a concoction of their 3rd qtr, 4th qtr, and Final Exam grades weighted 40, 40, 20 respectively.  Pretty straightforward I thought.

Sister : IT Guy, I can’t change my weighting.
IT Guy: Did you click the “Change” button?
Sister: No, should I try it?
IT Guy: yep, let’s give it a go
Sister: It didn’t work
IT Guy: What do you mean it didn’t work?  Was there an error message?
Sister: Yeah, do you want me to read it?
IT Guy: No, thanks……I can see it through the phone
Sister: Oh, ok………………….it says “invalid, expected integer”
IT Guy: Did you put a number in the box?
Sister: Yep!
IT Guy: I think I’ll come down for this one

IT Guy: Well Sister, here is the problem.  It turns out ” 1  100.00.00″ is not an integer.  In fact no number known to man starts with a space, has intermittent spaces through out and has 2 decimal points.  Why is you final exam worth  1  100.00.00 when everyone else’s is worth 20%

Sister: Oh, I see……how did I do that?
IT Guy: I don’t know, Sister.  It’s truly a mystery.