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Topic: SED ruling on the password problem
Replies: 9   Last Post: Jun 17, 2012 12:32 PM

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Evan Romer

Posts: 168
Registered: 1/8/09
SED ruling on the password problem
Posted: Jun 16, 2012 7:52 PM
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On the password problem (#39 maybe?) we called with two questions:

Q: For the second password, if the student does 9*9*9*9*9*9 instead of
10*10*10*10*10*10, is that a conceptual or computation error?

SED: Conceptual, 2 points off.

Q: On the last part, is the explanation, "second method, because it
makes more passwords" sufficient?

SED: Yes


I thought the first ruling was too harsh and the second too lenient.

True, idea that 0 is a digit is an important concept: it's just the
foundation of the Arabic system of numeration. But in the context of
this problem, this error was worth 50% off? Really? So a student who
does everything right for the two kinds of passwords and does the last
part right gets 2 out of 4?? The same as a student who doesn't
understand the difference between with duplication and without?

For the explanation, it seems to me that the student needs to refer to
the number of passwords needed, and say something about there being
NOT ENOUGH of the first type and that there ARE ENOUGH of the second
type. Just because there are more of the second type doesn't make it

Evan Romer
Susquehanna Valley HS
Conklin NY
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