UPSC NDA Math Model Paper 6

Clearly, there are 2 ways of answering each of the 5 questions i.e true or false
∴ Total number of different sequence of answers = 2 × 2 × 2 × 2 × 2 = 32
There is only one all correct answer sequence
So, the maximum number of sequences except the all correct answer sequence = 32 - 1 = 31
∵ different students have given different sequence of answers, so the maximum possible number of students = 31