Question
Question: In an examination, there are three multiple choice questions and each question has 4 choices. Number...
In an examination, there are three multiple choice questions and each question has 4 choices. Number of sequence in which a student can fail to get all answers correct is –
A
11
B
15
C
80
D
63
Answer
63
Explanation
Solution
No. of ways of attempting I, II, III questions are 4 each.
Total no. of ways= 4 × 4 × 4 = 64
no. of ways of getting all correct answer
= 1 × 1 × 1 = 1
no. of ways of not getting all answers all answers correct
= 64 – 1 = 63