document.write( "Question 1042801: A true/false test has 4 questions. What is the probability of getting at least 3 right by guessing the answers randomly? \n" ); document.write( "
Algebra.Com's Answer #657860 by MathTherapy(10551)\"\" \"About 
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A true/false test has 4 questions. What is the probability of getting at least 3 right by guessing the answers randomly?
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Probability of getting at least 3 means the probability of getting 3 or the probability of getting 4 correct. 
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document.write( "Use the BINOMIAL PROBABILITY formula: \"%22+%22%5Bn%5DC%5Bs%5D+%2A+p%5Es+%2A+q%5E%28n+-+s%29\"
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document.write( "Probability of getting 3 correct:  
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document.write( "Probability of getting 4 correct:  
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document.write( "Probability of getting at least 3 correct (probability of getting 3 or 4 correct): \"highlight_green%28matrix%281%2C3%2C+.25+%2B+.0625%2C+or%2C+highlight%28.3125%29%29%29\"
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document.write( "OR
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document.write( "Use the BINOMCDF feature on a calculator (e.g. TI-83/84). Enter: binomcdf(4,.5,1). You should also get \"highlight%28.3125%29\"
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document.write( "OR
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document.write( "Use MS Excel. Enter: \"=1-binomdist(3-1,4,.5,1.\" You should also get the above answer. \n" );
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