document.write( "Question 549998: in a certain school,of every 100 students selected, 20 of them have visited the sick bay. If 10 students were selected at random from a class find the probability that i)exactly 3 have visited the sick bay ii)at least 4 have visited the sick bay iii) at most 4 have visited the sick bay \n" ); document.write( "
Algebra.Com's Answer #358296 by stanbon(75887)\"\" \"About 
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in a certain school,of every 100 students selected, 20 of them have visited the sick bay.
\n" ); document.write( "So p(visited) = 1/5 : p(did not) = 4/5
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\n" ); document.write( "If 10 students were selected at random from a class find the probability that
\n" ); document.write( "So n = 10
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\n" ); document.write( "i)exactly 3 have visited the sick bay
\n" ); document.write( "P(x = 3) = 10C3*(1/5)^3*(4/5)^7 = 0.2013
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\n" ); document.write( "ii)at least 4 have visited the sick bay
\n" ); document.write( "P(4<= x <=10) = 1-binomcdf(10,1/5,3) = 0.1209
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\n" ); document.write( "iii) at most 4 have visited the sick bay
\n" ); document.write( "P(0<= x <=4) = binomcdf(10,1/5,4) = 0.9672
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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