SOLUTION: An examination consists of 10 multiple choice questions, each with 5 choices, 1 is correct and 4 incorrect. How many ways can a student mark the answers to these questions marking

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Question 269139: An examination consists of 10 multiple choice questions, each with 5 choices, 1 is correct and 4 incorrect. How many ways can a student mark the answers to these questions marking all 10 questions incorrectly?
Answer by dabanfield(803) (Show Source):
You can put this solution on YOUR website!
For each question there are 4 ways to select a wrong answer. Using the rule that says if event A occurs in m ways and event B occurs in n ways then A and B can occur together in m*n ways we know that wrongly answering question 1 occurs in 4 ways. For each to these ways there are 4 ways to wrongly answer question 2 and so on for questions 3 through 10. So for the number of ways to wrongly answer ten times we have:
4*4*4*4*4*4*4*4*4*4 = 4^10