document.write( "Question 1171367: In a high school mathematics exam, 72% of the students score grade B and below while the remaining 28% score A. Among those students who score grade A, 23% are female while 53% of the grade B and below students are female.
\n" ); document.write( "Let R= students who score B or lower, L= students score A, F= student is female. A student is selected randomly from the class.
\n" ); document.write( "i) Calculate the probability that the student is female.
\n" ); document.write( "ii) Is L independent of gender?
\n" ); document.write( "iii) Given that the student selected is female, calculate the probability that she is scoring B or lower.
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Algebra.Com's Answer #796340 by Boreal(15235)\"\" \"About 
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Look at 100
\n" ); document.write( "=======L===== R=====Total
\n" ); document.write( "M------21.56----33.84---55.4
\n" ); document.write( "F-------6.44-----38.16---44.6
\n" ); document.write( "Total---28-------72-------100\r
\n" ); document.write( "\n" ); document.write( "Randomly from the class, 0.446 probability female
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\n" ); document.write( "P(M)*P(L) should equal P(M&L)
\n" ); document.write( "0.155 should equal 0.2156. They do not.
\n" ); document.write( "Score is not independent of gender
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\n" ); document.write( "Given female (44.6), 38.16 were R for 0.8556 probability.
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