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- #1

#### Monoxdifly

##### Well-known member

- Aug 6, 2015

- 271

- Thread starter Monoxdifly
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- Thread starter
- #1

- Aug 6, 2015

- 271

- Jan 29, 2012

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We need to clarify. Are the 13 possible questions for #1 distinct from the 21 possible questions for #2? There are no questions in two different question pools? If so then, by the "fundamental counting principle", the number of tests, differing by at least one question, is 13(21)(14)(21).

I have no idea where you got "18 x 13 x 10". Also those are not "permutations" since you are not changing the order of the questions.

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- #3

- Aug 6, 2015

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