<PRE><B>Question 764227</B>
If one is guessing, then the probability of getting a correct answer is 1/2 and the probability of getting an answer wrong is also 1/2.
Probability that the first 7 answers are correct is (1/2)^7 = .008
Probability that the last three answers are false is (1/2)^3 = .125
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a)  sum the two probabilities, .008 + .125 = .133
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b) answer is no - because there are multiple ways to get 7 answers correct when guessing:
there are 7 ways to get a passing grade by guessing
   7        0        0        3
   6        1        1        2
   5        2        2        1   
   4        3        3        0
   3        1        4        2
   2        2        5        1
   1        3        6        0
multiply 7 times .008 = .056

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