SOLUTION: erica does not know the answers to 5 true/false questions on a test. If she randomly selects the answers, what is the probability that she will answer the first, third, and fourth

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Question 953338: erica does not know the answers to 5 true/false questions on a test. If she randomly selects the answers, what is the
probability that she will answer the first, third, and fourth questions correctly and the other questions incorrectly?
i know i am making this more complicated than it really is but i just cannot figure it out

Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
consider the following
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for question 1 there are 2 ways to answer it (T, F)
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for question 2 and 1 there are 4 ways to answer (T, T), (T, F), (F, T), (F, F)
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for question 3, 2, and 1 there are 8 ways to answer (T, T, T), (T, T, F), (T, F, T), (T, F, F), (F, T, T), (F, T, F), (F, F, T), (F, F, F)
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the pattern 2^n represents the number of ways at each question n, therefore
for n = 5, 2^5 = 32
there is only one way for (T, F, T, T, F) to occur, therefore
the probability for (T, F, T, T, F) = 1/32