document.write( "Question 1143882: A company owns a fleet of 20 cars, each having either manual or automatic transmission and either 2 or 4 doors. It is reported that 13 cars are 2-door models and, of these, 12 have automatic transmission. There are only 4 cars with manual transmission. If a car is picked at random from a fleet, calculate the probability that it is:
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Algebra.Com's Answer #764812 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "(1)  Consider first statement of the problem:\r\n" );
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document.write( "          Of the total fleet of 20 cars, 13 cars are 2-doors.  \r\n" );
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document.write( "     From this statement,  20-13 = 7 cars are 4-doors.\r\n" );
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document.write( "(2)  Consider the second and the third statements:\r\n" );
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document.write( "         of the 13 2-doors cars, 12 have automatic transmission (AT).\r\n" );
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document.write( "         There are only 4 cars with manual transmission (MT).\r\n" );
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document.write( "     From these two statements, one can make the following conclusions:\r\n" );
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document.write( "         - Of the 13 2-doors cars, 1 has manual transmission;\r\n" );
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document.write( "         - of the  7 4-doors cars, 3 have manual transmission and 4 have automatic transmission.\r\n" );
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document.write( "Let us ORGANISE this information.\r\n" );
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document.write( "    There are  13 2-doors cars; of them, 12 have AT and 1 have MT.\r\n" );
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document.write( "                7 4-doors cars; of them,  4 have AT and 3 have MT.\r\n" );
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document.write( "Now I am in the position to answer problem's questions.\r\n" );
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document.write( "    (A)  P = .                  ANSWER\r\n" );
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document.write( "    (B)  P =  =  = .    ANSWER\r\n" );
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document.write( "The key in solving this problem is to organize and to present the information in a compact and clear logical form.\r\n" );
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document.write( "To get it, you need to extract / (to deduce) all logical consequences from the given info.\r\n" );
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document.write( "Surely, it is assumed, that you firmly know this formula for the conditional probability\r\n" );
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document.write( "    P( M | N ) = ,\r\n" );
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document.write( "where M and N are subsets of the universal set.\r\n" );
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