Question
Mathematics Question on permutations and combinations
In an examination, there are three multiple choice questions and each question has 4 choices. Number of ways in which a student can fail to get all answers correct is
A
11
B
12
C
27
D
63
Answer
63
Explanation
Solution
There are three multiple choice questions, each has four possible answers. Therefore, the total number of possible answers will be 4×4×4=64. Out of these possible answers only one will be correct and hence the number of ways in which a student can fail to get all correct answers is 64−1=63.