SOLUTION: I need assistance with this homework:
A test consists of 10 true-or-false questions. An answer is randomly chosen for each question.
What is the probability of answering exact
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-> SOLUTION: I need assistance with this homework:
A test consists of 10 true-or-false questions. An answer is randomly chosen for each question.
What is the probability of answering exact
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Question 429565: I need assistance with this homework:
A test consists of 10 true-or-false questions. An answer is randomly chosen for each question.
What is the probability of answering exactly 4 questions correctly? Answer in fraction.
What is the probability of answering at least 2 questions correctly? Answer in fraction. Answer by ewatrrr(24785) (Show Source):
Hi
Note: The probability of x successes in n trials is:
P = nCx* where p and q are the probabilities of success and failure respectively.
In this case p & q are = 1/2 or .5
nCx =
10 true/false questions:
P(answering exactly 4 correct)= 10C4(.5)^4(.5)^6 = 210(.5)^4(.5)^6
P(of answering at least 2 questions correctly) = 1 -P(none) -P(one)
1 - (.5)^10 - 10(.5)(.5)^9
