document.write( "Question 1021428: Michael has a drawer containing lots of AA batteries. There are 6 Energizer batteries, 5 Duracell batteries, and 4 Panasonic batteries. If he reaches in and randomly selects 2 batteries, what is the probability they are the same brand? \n" ); document.write( "

Algebra.Com's Answer #637159 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi  
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document.write( "15 batteries: 6E, 5D, 4P
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document.write( "'Chose' 2
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document.write( "P(the same brand) = [6C2 + 5C2 + 4C2]/15C2 = [ 15 + 10 + 6]/105 =  [31]/105= .2952 = 29.52%
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document.write( "note: 6C2 = 6!/2!4! = 6*5/2 = 15 \n" );
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