7.
In a test, 5 questions are of the form 'state,
true or false'. No student has got all answers
correct. Also, the answer of every student
is different. Find the number of students
appeared for the test.
Not to give spam answer
Answers
Answered by
6
Answer:
31 students
Step-by-step explanation:
Since there are 5 questions and each question has two options, therefore total permutations of the true or false options that are possible are
=2\times 2\times 2\times 2\times 2\times 2=2×2×2×2×2×2
=2^5=2
5
=32=32
Out of these 32 possibilities, one is the correct one
But no students has got a correct answer
Therefore, the number of students that must have taken the test
=32-1=32−1
=31=31
Therefore, there are 31 students.
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