SOLUTION: A professor writes 40 discrete mathematics true/false questions. Of the statements in these questions, 17 are true. I f the questions can be positioned in any o

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Question 522406: A professor writes 40 discrete mathematics true/false
questions. Of the statements in these questions, 17 are
true. I f the questions can be positioned in any order, how
many different answer keys are possible?

Found 2 solutions by stanbon, sudhanshu_kmr:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A professor writes 40 discrete mathematics true/false
questions. Of the statements in these questions, 17 are
true. I f the questions can be positioned in any order, how
many different answer keys are possible?
----------
# of arrangements of the 40 questions: 40!
----
# of answer patterns for the 40 questions: 2^40
-----
Total # of keys possible: 40!*2^40
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Cheers,
Stan H.
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Answer by sudhanshu_kmr(1152) About Me  (Show Source):
You can put this solution on YOUR website!

Answer of 17 questions are true and answer of 23 questions are false.

Total number of possible different answer keys = 40!/[17!*23!]
= 88732378800

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