document.write( "Question 1143802: 30 students -26 are right handed, 10 walk to school and 9 of the walkers are right- handed.
\n" ); document.write( "Find the probability that a student chosen at random;
\n" ); document.write( "i) is left-handed and walks to school
\n" ); document.write( "ii) is left-handed, if we know the student walks to school
\n" ); document.write( "iii) does not walk to school if we know the student is left-handed \n" ); document.write( "

Algebra.Com's Answer #764717 by ikleyn(52786) $\"\"$ $\"About$

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document.write( "From this fragment of the condition  \". . . 10 walk to school and 9 of the walkers are right-handed\" \r\n" );
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document.write( "one may conclude that one (and only one) of 10 walking to school is left-handed.\r\n" );
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document.write( "Therefore, the answer to  i)  is  P =  = 0.1 = 10%,   and \r\n" );
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document.write( "           the answer to  ii) is  P =  = 0.1 = 10%.\r\n" );
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document.write( "Next, since of 30 students 26 are right-handed (given), it means that 4 = 30-26 are left-handed.\r\n" );
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document.write( "Of these 4 left-handed, only one walks to school, as we established ABOVE.\r\n" );
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document.write( "Hence, the rest  4-1 = 3 left-handed do not walk to school, giving answer to iii) :\r\n" );
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document.write( "    P (does not walk to school if we know the student is left-handed) =  =  = 0.1 = 10%.\r\n" );
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