document.write( "Question 368494: 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? \n" ); document.write( "

Algebra.Com's Answer #262586 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi,
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document.write( "Note: The probability of x successes in n trials is: 
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document.write( "P = nCx*  where p and q are the probabilities of success and failure respectively. 
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document.write( "In this case both p & q are = 1/2 or .5
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document.write( "nCx = 
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document.write( "A test consists of 10 true-or-false questions
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document.write( "P (exactly 4 correctly)= 210*(.5)^4 (.5)^6 = .205 \n" );
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