How many different answer keys are possible? A professor writes $40$ discrete mathematics true/false questions. Of the statements in these questions, $17$ are true. If the questions can be positioned in any order, how many different answer keys are possible?
No. of questions=40. so, 40! ways of arrangements.
No. of ways of arranging answers= 2^40( two choices true and false)
total no. of keys possible= 40!*2^40
No. of questions=40. so, 40! ways of arrangements.
No. of ways of arranging answers= 2^40( two choices true and false)
total no. of keys possible= 40!*2^40