Questions: Multiple-choice questions each have five possible answers (a, b, c, d, e), one of which is correct. Assume that you guess the answers to three such questions.
a. Use the multiplication rule to find P(WWC), where C denotes a correct answer and W denotes a wrong answer.
P(W W C)=
(Type an exact answer.)
Transcript text: Multiple-choice questions each have five possible answers ( $a, b, c, d, e$ ), one of which is correct. Assume that you guess the answers to three such questions.
a. Use the multiplication rule to find $\mathrm{P}(\mathrm{WWC}$ ), where C denotes a correct answer and W denotes a wrong answer.
\[
P(W W C)=
\]
$\square$ (Type an exact answer.)
Solution
Solution Steps
Step 1: Identify the Sequence of Guesses
Given a sequence of guesses 'WWC', where 'C' represents a correct guess and 'W' represents a wrong guess.
In this sequence, there are 1 correct guesses and 2 wrong guesses.
Step 2: Calculate the Probability for a Correct Guess
The probability of guessing a question correctly is \(\frac{1}{5}\), since there is one correct answer out of 5 possible answers.
Step 3: Calculate the Probability for a Wrong Guess
The probability of guessing a question incorrectly is \(\frac{4}{5}\), since there are 4 wrong answers out of 5 possible answers.
Step 4: Use the Multiplication Rule
To find the probability of the given sequence 'WWC', we multiply the probabilities of each event in the sequence together.
The probability is \(\left(\frac{1}{5}\right)^{1} \times \left(\frac{4}{5}\right)^{2}\).
Final Answer:
The probability of guessing the sequence 'WWC' correctly is 0.128.