Question:
In an examination there are three multiple choice questions and each question has four choice. The number of ways in which a student can fail to get all answers correct, is __________.
Solution:
Since each question has 4 options
i.e there are 4 choices or 4 ways to answer a question
∴ Number of ways to answer 3 questions is 4 × 4 × 4 = 64
Out of 64 ways, there is only one way which has all the answer correct.
So, number of ways in which a student fails to get all answer correct is 64 − 1 = 63 ways.