document.write( "Question 388848: There are 21 students in Mrs. Smith’s algebra class. Mrs. Smith randomly chooses 3 students to work problems on the board each day. What is the probability that Carly will be asked to work a problem today if one student is absent? \n" ); document.write( "
Algebra.Com's Answer #275248 by stanbon(75887)\"\" \"About 
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There are 21 students in Mrs. Smith’s algebra class. Mrs. Smith randomly chooses 3 students to work problems on the board each day. What is the probability that Carly will be asked to work a problem today if one student is absent?
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\n" ); document.write( "1 - P(all three are chosen from the remaining 19 students)
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\n" ); document.write( "= 1 - 19C3/20C3
\n" ); document.write( "= 1 - 0.85
\n" ); document.write( "= 0.15
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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