A quiz consists of 20 true-false questions. The score for each question is 1 point if it is answered correctly, and 0 otherwise. To get an A grade on the test, you need a total score of more than 16 points. One of the students knows the correct answer to 6 of the 20 questions. The rest she guesses at random by tossing a coin (one toss per question). What is the chance that she gets an A grade on the test?

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anonymous · Answer

Suppose a student guesses the answer to Question 1 on the test by tossing a coin: if the coin lands Heads, she answers True, and if it lands Tails, she answers False. What is the chance that she gets the right answer? please the answer